1^ 


PRESENTED  TO 

TtieiimTyofciiyfoiiii 

BY  I 

KDMONI)  L.  GOOLI). 


an 


tn 


^ 


in 


00 


\i 


^         Co 


Digitized  by  the  Internet  Archive 

in  2008  with  funding  from 

IVIicrosoft  Corporation 


http://www.archive.org/details/bottomofseaOOsonrrich 


THE 

BOTTOM   OF  THE   SEA, 


Ruins  of  the  Teni[>le  of  Hercules  at  (abraltai 


THE 


BOTTOM  OF  THE  SEA. 


By    L.    SONRE 


TRAh'SLATED    AND    EDITED    BY 

ELIH  U    RICH, 

rRANSLATOK  OF   CAZIN'S    POPULAR    TREATtSE   ON    "THE    PHENOMUINA    ANL 

v-Aws  OK  heat;"  late  editor  of  "the  people's  MAGAZINK," 

ETC.,    ETC. 


NEW    YORK: 

CHARLES    SCRIBNER    AND    CO. 

1870. 


Illustrated  pibrary  of  <^i'Onders 


PUBLISH i:l>    I!Y 


mn.  ^harles  .^tribntr  i^  ^o., 


654  BROADWAY,  NKW  YOIJK. 

Each  one  volume  12mo.  Price  per  volume,  '^\.-)0. 


Titles  of  Books. 

Thunder  and  LiGnxNiNfi,     . 

WoNDEi:s  OF  Optics, 

WoNDEKS  OF  Heat. 

Intelligence  of  Animals, 

Geeat  Hunts,     . 

Egypt  3,300  Years  Ago,     . 

Wonders  of  Pompeii, 

The  Sun,  by  A.  Guillemin, 

Sublime  in  Nature,     . 

Wonders  op  Glass  Making, 

Wonders  OF  Italian  Art, 

Wonders  op  the  Hqman  Body, 

Wonders  of  Architecture, 

Lighthouses  AND  Lightships, 

Bottom  of  the  Ocean, 

Wonders  of  Bodily  Strength  and 

Wonderful  Balloon  Ascents, 

Acoustics. 

Wonders  op  the  Heavens,    . 

The  Moon,  by  A.  Guillemin. 

Wonders  op  iSculpturb, 

Wonders  op  Engraving, 

Wonders  op  Vegetation, 

Wonders  op  the  Invisible  World. 

Celebrated  Escapes. 

Water.  .... 

Hydraulics. 

Electricity, 

Subterranean  World, 


In  Press  for  early  Publication. 


So.  of  IllKstratinns 


50 
63 
28 
45 
5' 
60 
fiS 
70 
30 
114 
48 
6) 
01 
32 
45 
i>7 
26 
77 
40 
71 
27 


The  above  works  sent  to  any  addras^,,  pa-it  paid,   upon  receipt  of  the  price  ht, 
piiblishern. 


TRANSLATOR'S   PREFACE. 


This  little  book  supplies  a  general  and  instructive 
outline  of  a  certain  number  of  interesting  facts  con- 
nected with  the  sea.  It  bears  the  same  relation  to 
the  strictly  scientific  treatment  of  the  subject  as  a 
popular  lecture  on  art  to  instruction  in  the  studio, 
a  ramble  through  a  museum  to  a  lecture  on  science ; 
or  a  short  pleasure-sail  on  the  coast,  with  here  and 
there  an  opening  glimpse  of  the  scenery,  and  a 
pleasant  chat  on  the  wonders  of  the  deep,  to  an  ac- 
curate survey  and  a  formal  report  on  the  same  sub- 
jects. Occasionally,  it  may  be  hoped,  the  reader  will 
find  something  more  in  the  following  chapters  on 
*'  The  Bottom  of  the  Sea,"  than  these  remarks  would 
lead  him  to  suspect ;  but  its  pretentions  are  not  such 
as  would  justify  the  kind  of  criticism  which  a  scien- 
tific treatise  like  that  of  Professor  Tyndall's  book  on 
Heat,  and  many  works  of  less  scientific  importance, 
are  rightly  supposed  to  challenge. 

Our  knowledge  of  the  sea  is  not,  indeed,  so  exact 
as  to  justify  the  same  high  pretensions  to  accuracy, 


vi  TRANSLATOR'S  PREFACE. 

even  in  a  strictly  scientific  elucidation,  of  which 
many  other  investigations  admit;  and  yet,  as 
Franklin  observed  in  his  time,  what  persevering 
efforts  have  been  made  to  master  the  secrets  of  the 
abyss,  and  what  dangers  have  been  enconntered  in 
the  struggle  of  man  with  its  gigantic  forces! 
Michelet  commences  his  well-known  book  on  the 
subject  by  remarking  that  the  first  impression  which 
man  receives  from  the  Ocean  is  one  of  dread ;  but 
if  this  observation  be  just,  that  dread  of  the  vast 
and  unknown  has  in  all  ages  been  converted  into  a 
source  of  inspiration,  until  men  of  genius  have 
achieved  their  greatest  triumphs  where  they  feared 
the  most.  Some  of  these  achievements  are  remarked 
upon  in  the  following  pages.  But  the  complete 
record  of  similar  conquf  sts  would  fill  a  volume,  for 
it  is  always  on  the  shores  of  the  sea,  and  by  means 
of  the  sea,  that  men  have  established  their  communi- 
ties, and  spread  their  civilisation  over  the  earth.  The 
sea,  not  dreaded  but  loved,  and  used  as  a  mighty 
agency,  is  truly  the  '*  Vita  Nuova  of  Nations." 

While  touching  slightly  on  this  topic,  and  avoiding 
the  dryness  of  scientific  details,  this  book  will  be 
found  to  give  a  general  idea  of  the  configuration  of 
the  sea-bottom,  of  the  action  of  the  sea  upon  its 
shores,  and  of  some  of  the  more  impressive  wonders 
of  the  deep.     The  reader,  hitherto  uninitiated  intc 


TRANSLATOR'S  PREFACE.  ix 

this  branch  of  study,  will  find,  in  conclusion,  that  he 
has  learned  somewhat  of  the  great  law  of  perpetual 
motion  and  change  in  what  he  may  have  previously 
deemed  the  immoveable  crust  of  the  earth.  He  will 
have  learned  to  regard  the  mystery  of  that  movement 
with  a  measure  of  the  same  awe  that  is  inspired  by  a 
study  of  the  distant  nebulae ;  and  he  will  have  felt  how 
essential  it  is,  in  studies  of  this  nature,  to  disembar- 
rass his  mind  of  ideas  borrowed  from  limited  views  of 
the  measurements  of  time  and  space  : 

God  worketh  slowly ;  and  a  thousand  years 
He  takes  to  lift  His  liand  off 


MUSWELL   Hi IX, 

January,  1870. 


CONTENTS. 


SUBMARINE  OROGRAPHY. 

PAflB 

1.  The  plummet — Brooke's  deep-sea  sounding  apparatus       .       1 

2.  Construction  of  charts  and  sections  of  the  ocean-bottom — 

But  little  as  yet  known  of  this  subject — Maury,  the 
founder  of  submarine  orographic  science        ...       8 
'^.  Analogy  between  the  configuration  of  continents,  and  that 

of  the  bottom  of  the  sea — Equatorial  section  of  the  earth     18 

4.  Northern  Atlantic  Ocean— Chart  of  Maury       .         .         .27 

5.  The  Mediterranean  and  the  Black  Seas — Chart  of  Biittger     31 

6.  The  Baltic— The  North  Sea— The  Straits  of  Dover— The 

English  Channel— The  Bay  of  Biscay  .         .         .37 

thh;,  watkr  of  the  ocean. 

1.  Composition  of  sea- water — Biot's  apparatus      .         .         .42 

2.  Variations  in  the  saltness  of  sea-water  •    .         .         .         .47 

3.  Variations  observed  in  the  gases  contained  in  sea-water     .     52 

4.  Solid  bodies  in  the  sea — Phosphorescence  .         .         .55 

5.  Colour  of  sea-water — To  what  extent  influenced  by  matters 

held  in  suspension,  by  the  bottom  of  the  sea,  and  by  the 
agitation  of  the  water  ......     6!i 

6.  Measure  of  temperature  at  the  bottom  of  the  sea        .         .     68 

7.  Diminished  temperature  of  the  sea  in  proportion  to  the 

depth — Irregularities  introduced  in  this  law  by  the  in- 
fluence of  submarine  currents  —  Temperature  at  the 
bottom  of  the  ocean  constant  and  uniform — Principal 
causes  of  submnrine  currents        .  .  .          .  .70 


xii  CONTENTS, 

PACK 

8.  Cause  of  waves — Their  height — Thickness  of  the  mass  of 
water  in  motion  —  Ground-swells — "  Raz  de  Maree" — 
Waves  of  translation — Measure  of  a  wave  of  translation, 
and  of  its  speed,  in  the  Pacific  Ocean — Tides — Resume       74 


DEPOSITS  IN  COURSE  OF  FORMATION  AT  THE  BOTTOMS 
OF  SEAS. 

1.  Universality  of  the  process  of  sedimentation — General  view 

of  the  mechanism  of  this  phenomenon  .         .         .         .80 

2.  Action  of  waves  upon  the  coasts — Destruction  of  rock- 

bound  shores  by  the  sea — Pierced  rocks — Silting-up  of 
shallow  waters  by  marine  alluvium      .         .         .         .     b9 

3.  Deposits  in  mid-ocean,  and  deposits  on  the  coasts — Im- 

portance to  geologists  of  coast-deposits  as  data  for  fixing 
the  limits  of  ancient  seas  —  Deposits  of  the  French 
seas  .........     94 

4.  Transport  and  deposit  of  rocks  by  floating  ice  .         .         .     99 

5.  Water-springs  in  the  earth — Funnels  or  wells  of  the  Jura 

— The  Aveii  of  the  South  of  France — Katavotron — Sink- 
holes— Geysers — Submarine  springs — Origin  of  oolitic 
formations .102 

SUBMARINE  LIFE. 

1.  Exuberance  of  life  in  the  depths  of  the  ocean — Tableau*  of 

the  tropical  seas — Life  in  the  seas  of  the  temperate 
and  the  frozen  2;pnes — Natural  illumination  of  the 
oceanic  abysses  .         .         .         .         .         .         .   1 09 

2.  Migration  of  marine  animals — Nests  at  the  bottom  of  the 

sea — Fisheries 124 

3.  Terrible  conflicts  of  marine  monsters — Massacre  of  the  weak 

by  the  strong     ...  ....  142 

4.  Animated  forests — Animal  stones 161 

5.  Sponges        .........  165 

6.  Polypi — Their  general  structure — ^Reproduction  of  polypi — 

Vegetative  life  of  polypi  —  The  polypier— Two  great 
classes  of  polypi  distinguished  by  the  form  of  the 
polypier — The  Tubipora  musica 170 


CONTENTS.  xiii 

TAGK 

7.  Hydra,  type  of  the  hydrozoa  or  hydra  polyps — Extraor- 

dinary properties  of  the  hydra  discovered  by  Trenibley — 
Marine  hydrozoa         .......   170 

8.  Actiniffi — Sea-anemones — Sea-nettles        .         .         .         .184 
0.  Coral — Miraculous  virtue  attributed  to  coral  by  ancient 

tradition— Coral  stone — Coral  plant — Marsigli  discovers 
the  flowers  of  the  coral— rObservations  of  M.  Lacaze- 
Duthiers 186 

10.  Coral  chiefly  found  in  the  Mediterranean   Sea — Various 

species  of  coral — The  coral  fishery — Antipathes,  com- 
monly called  black  coral      ......  189 

11.  Gorgons  of  the  old  writers — Their  animal  nature  discovered 

by  Peyssonnel,  Trt-mbley,  and  Bernard  de  Jussieu — The 
fan-gorgon — Its  cosmopolitan  character         .         .         .   191 

1 2.  The  more  active  submarine  constructors — Astroides — Curyo- 

phillia — Madrepora  i)lantjginta — Dendrophyllia — Occu- 
lina,  or  white  coral — Meandrina — ^Fungia — Pontes — 
MilleporsB 195 

18.  r*  alley-slaves  of  the  sea — The  giants  and  pigmies  of  crea- 
tion— The  suckers — Legends  of  monsters — Singing  fishes  207 

N.  Algae — The  untrodden  forests  and  prairies  of  the  ocean — 
Animal  life  more  abundant  than  vegetable  life — Sea- 
plants  kss  widely  distributed  than  marine  animals — 
Influence  of  lii;ht — Collection  of  seaweed  on  the  coasts 
— ^Assistance  aftbrded  by  the  tide         ....  224 


MAN  AND  HIS  WORK  AT  THE  BOTTOM  OF  THE  SEA. 

1.  The  empire  of  the  seas  denied  to  man — Numerous  attempts 

at  submarine  exploration — Disturbance  of  present  social 
conditions  which  would  ensue  from  the  possibility  of 
travelling  beneath  the  surface  of  the  water — The  sea  the 
best  tie  between  nations      ......  231 

2.  Exploration  of  the  bottom  of  the  sea — Diving  apparatus — 

Invention   of  MM.  Rouquayrol  and  Denayrouze  — Sub- 
marine electric  illumination — Salvage  of  objects  sunk  in 
the  sea — A  chest  of  gold  reoovere  1  under  peculiar  cir- 
cumstances in  th«5  port  of  Marseilles    ....   243 
i.  Cowan's  s:ilvage  of  Rusbiun  vessels  in  Sebastopol  Harbour    255 


xiv  CONTENTS. 

PAOE 

4.  Ships  repaired  without  leaving  the  water,  and  even  while 

under  sail  ........  259 

5.  Sensations  of  the  diver — Depth  to  which  it  is  possible  to 

descend 26 1 

6.  Extreme  difficulty   of  working  below  water — Submarine 

foundations— Stone  worked  when  in  position  .         .  266 

7.  Diving-be}ls — Stationary  com[)ressed-air  apparatus   .         .  270 

8.  Payerne's  submarine  hydrostat         .....  274 
U.  VUleroy's  submarine  boat       ......  278 

10.  Employment  of  torpedoes  in  clearing  channels  and  the 

entrances  to  ports 280 

1 1 .  English  mines  beneath  the  ocean    .....  284 

CHANGES  IN  PROGRESS  AT  THE  BOTTOMS  OF  SEAS.— 
THEIR  UNIVERSALITY. 

1.  Extent  of  the  movements  of  the  terrestrial  crust — Nature 

incessantly  at  work — The  gradual  cooling  of  the  earth  a 
cause  of  its  present  form,  owing  to  the  crumpling  and 
breaking  of  its  crust 286 

2.  The  shore — Its  apparent  fixity — Traces  of  the  presence  of 

the  ocean  almost  universal  .....  295 

3.  Progressive  enlargement  of  the  Straits  of  Gibraltar  during 

the  historic  period — Columns  of  the  ancient  Temple  of 
Hercules  submerged  —  Descriptions  left  by  Avienus, 
Pliny,  and  Pomponius — Mellaria,  Carteia,  and  Belon 
submerged — Other  examples  of  cities  and  islands  covered 
by  the  waters,  and  of  mountains  violently  separated 
from  continents  .......   298 

4.  The  quantity  of  water  which  covers  the  earth  is  sensibly 

constant — An  elevation  in  one  point  is  balanced  by  a 
coiresponding  subsidence  in  another — Aristotle's  opinion 
about  the  Greek  traditions  of  the  Deluge — The  earth  will 
become  dryer  and  colder      ......  304 


SUDDEN  MOVEMENTS  OF  THE  SUBMARINE  SOIL. 

I.  Earthquakes  modify  the  bed  of  the    ocean— Submarine 

volonnoes  ........   308 


CONTENTS.  XV 

fagb 

2.  Greek  Archipclagf) — Delos  and  Rliodes  upheaved  from  the 

bottom  of  tlie  sea — Succt-Ssive  additions  to  the  Archi- 
pelago of  Santorin      . 310 

3.  The  Azores — Appearance  and  disappearance  of  islands  sub- 

sequent to  earthquakes — The  ephemeral  island  Sabrina  .  315 

4.  Submarine  volcano  in  the  middle  of  the  Atlantic       .          .   31S 

5.  Submarine  eruptions  near  Kamtschatka — Iceland — Ignited 

sea ;  appearance  of  an  island  near  Keikiancss — Uise  of  a 
fiery  island  from  the  ocean,  near  the  Aleutian  Isles         .  310 

6.  The  bottom  of  the  sea  feels  the  counterblow  of  terrestrial 

volcanic  phenomena   .......   322 

7    Products  of  submarine  volcanoes — How  they  differ  from 

the  pro  lucts  of  subaiirial  volcanoes  ....  324 
8.  Bottom  of  the  seu  brought  to  light  in  consequence  of  the 

eruption  of  submarine  volcanoes  ....  328 

GRADUAL  CHANGES  OF  THE  BOTTOM  OF  THE  SEA. 

1.  How  the  gradual  change  of  the  sea-bottom  can  be  demon- 

strated— Modifications  which  the  map  of  Europe  would 
suffer  by  a  gradual  subsidence  of  thirty  feet  in  a  century — 
Paris  submerged — Europe  as  it  would  be  were  the  level 
of  the  seu  raised  500  feet — Toulouse  and  Vienna  as  sea- 
ports        .........  331 

2.  Ancient  liuiits  of  the  Black  Sea — Drying-up  of  the  Russian 

steppes      .........   H38 

3.  Movements  of  the  earth  in  tlie  northern  himispherc — Sub- 

sidence in  the  north  of  Europe  and  of  America — Elevation 

of  the  polar  regions — Sinking  of  the  coast  of  Sweden     .   o4() 

4.  Elevation  of  Spitzbergon — Sinking  of  the  western  coast, 

and  elevation  of  the  eastern  coast  of  Greenland — Gradual 
submersion  of  the  forests  of  Labrador  and  of  Nova  Scotia 
— Roman  constructions  engulfed  in  the  Low  Countries 
—  Origin  of  the  Zuyder  Zee — Failure  of  the  Dutch  sea- 
dams — Tii»-  Valley  of  the  Somme  and  the  coa.st.s  of  Nor- 
mandy follow  the  movement  of  subsidence  of  the  Low 
Countries  ........  344 

R.  Two  extensive  zaies  of  subside»)ce  in  the  southern  hemi- 
sphere— They  aie  separated  by  a  zone  of  elevation — The 
Fiji  Islands  have  been  sinking  diiriig  300,000  years       .  347 


xvi  CONTENTS. 

ACTION  OF  RIVERS  AND  CURRENTS  ON  THE  I50TT0M 
OF  THE  SEA. 

l-AOB 

1.  Choking  of  ports  with  sand— Deltsis,  and  the  action  of  the 

tide  upon  them — The  formation  of  deltas  may  be  either 
favoured  or  retarded  by  marine  currents  according  to 
circumstances — Deltas  formed  in  shallow  seas — Rapid 
growth  of  the  delta  of  the  Po  due  to  the  clearing  of  the 
south  side  of  the  Alps,  and  to  the  damming-in  of  the 
shores  of  the  river 351 

2.  Egypt,  according  to  Herodotus,  a  present  from  the  Nile     .  357 

3.  Description  of  the  delta  of  the  Mississippi — A  village  at 

anchor — Ships  lost  in  the  sand  and  mud  of  the  river      .  360 

4.  Rapid  growth  of  the  deltas  of  the  Po  and  of  the  Mississippi 

— ^Delta  of  the  Nile  enlarged  by  seven  miles  during  the 
historic  period — The  Rhone 36P 

5.  Littoral  accumulations — Coast-line — Marine  lagoons  and 

pools — Lagoons  moved  inland  by  the  effects  of  the  dunes 
in  Gascony — Villages  buried  beneath  the  dunes  near 
St.  Pol-de-Leon  in  Brittany,  and  also  in  Gascony— 
Bordeaux  menaced     .         .         .         .         .         .         .371 

6.  Floating  icebergs — Polar  winters 37<-' 

INFLUENCE  OF  LIFE  ON  VARIATIONS  IN  THE  BED 
OF  THE  OCEAN. 

1.  Formation  of  coral  reefs  ;  limit  to  their  growth — Condi- 

tions favourable  to  their  development  ....  380 

2.  Life  and  inanimate  nature — Coral  insects  die  in  the  calm 

of  deep  waters — Explanation  of  the  formation  of  the  deep 
reefs  of  the  Pacific  Ocean— Coast  reefs — Broken  reefs — 
Barrier  reefs  of  Australia — How  the  coral  reef  becomes 
an  island 383 

3.  Slowness  of  the  growth  of  coral  reefs — Florida  Keys — De- 

struction of  coral  islands  during  a  tempest  in  January 
1865 — Regions  in  which  coral  reefs  are  found         .         .  390 

4.  Algae — Submarine  forests  and  prairies — Floating  seaweed 

of  the  Sargossa  seas — Extension  of  the  coasts  by  the  Rhi- 
zophora  Mangle  .......   393 

INSIGNIFICANCE  OF  MAN  COMPARED  WITH  THE  OCEAN   396 


LIST  OF  ILLUSTRATlOxXS. 


Ruins  of  the  Temple  of  Hercules  at  Gibmltur  Frnut 

1.  Mail's  conquests  of  Nature      ..... 

2.  Brooke's  deep-sea  sounding  apparatus 

3.  Striking  the  sea-bottom 

4.  Measuring  the  depth  of  the  sea  by  means  of  a  bomb  . 

5.  Vertical  section  of  tlie  Atlantic  from  Yucatan  (coact  of 

Mexico)  to  Senegal 


I'AOR 

\necfi 

vii 

4 


10 


G.  Sectcju  of  the  Atlantic  Ocean  from  Paris  to  Newfoundland    23 
7.  Equatorial  section  of  the  <!arth        .  .  .  .  .25 

.s.  Chart  of  the  depths  of  the  Atlantic  Ocean       .         .         .29 
9.  Chart  of  the  respoctivu  depths  of  the  Mediterranean,  the 

Adriatic,  and  the  Black  Seas 33 

10.  Depths  of  the  Adriatic 36 

11.  Profile  of  the  ocoan-floor  from  the  southernmost  point  of 

Norway,  via  the  Straits  of  Dover,  to  tlie  10th  degree  of 
west  longitude  and  the  47th  degree  of  north  hititude      .     39 

12.  Vertical  section  of  the  Straits  of  Dover     .         .         .         .40 

13.  Phosphorebcent  sea  at  Simon's  Town,  Cape  of  G()0<1  Hope      57 

14.  Incidence  of  the  rays  of  lij^ht  on  a  calm  sea      .  .66 

15.  Incidence  of  the  rays  of  liglit  on  the  waves  of  tlie  sea         .     67 

16.  Rising  of  the  sea  at  Acapulco 79 

17.  Waves  breaking  against  a  rock-bound  coast  .         .     90 

18.  Rocks  worn  througli  by  the  waves  .  .  .  .  .     !>'{ 

19.  Section  of  the  sea  and  the  sea-bottom  in  the  tratk  of  ii-o- 

l>org8  between  Greenland  ail' I  Vcwfiundland         .  .    100 

h 


LI6T  OF  ILLUSTRATIONS. 


20.  Cause  of  subtiiarine  springs    . 

21.  Dabs  and  soles 

22.  Poulpe,  or  cuttle-fish 

23.  The  hippocampus  . 

24.  Herrings  attucked  by  tunny-fish 

25.  Fight  between  a  swordfish  and  a  whale 

26.  Fight  between  a  tailor  and  a  shark 

27.  Turbots 

28.  Fishing  for  sponges  on  the  coast  of  Syria 

29.  Coral  with  polypi  more  or  less  expanded 

30.  Branch  of  coral  with  polypi  indrawn 

31.  Organ-pipe  coral  .... 

32.  Sea-pen  (Peniiatula  spinosa)  . 

33.  Veretillum  cynomorium 
tS4.  SpiculiB  of  coral    .... 

35.  Portion  of  the  fan-gorgon,  magnified 

36.  Dendrophyllia  ramea     . 

37.  Caryophillia  cyathus 

38.  Astrea  punctifera 

39.  Madrepora  plantaginea  . 

40.  Dendrophyllia  (half  the  natural  size) 

41.  Meandrina  cerebriformia 

42.  Milh  pora  alcicomis  (one-fourth  of  the  natural 

43.  Fungia  agariciforrais 

44.  Gneiss  bored  by  the  Pholades  dactylus 

45.  Malayan  divers  fishing  for  holothuria 

46.  Divers  dressed  in  the  apparatus  invented  by  MM 

quayrol  and  Denayrouze     . 

47.  Divers  finding  a  box  of  gold  in  the  port  of  Marseilles 

48.  Salvage  of  Russian  ships  sunk  at  Sebastopol 

49.  Caulking  a  ship  while  under  sail     . 

50.  Sinking  blocks  of  artificial  slone  at  Cherbourg 

51.  Vertical  section  of  breakwater  at  Cherbourg 
rvZ.  Div  ng-liell 


size) 


Kou- 


LIST  OF  ILLUSTKATWNS. 

53.  Fixed  apparatus,  supplied  with  conipr  ssod  ni 

54.  Payerne's  submarine  hydrrstat 

55.  Villeroy's  submarine  boat        ... 

56.  Kemoving  an  ol  struction  by  means  of  u  torped< 

57.  Section  of  a  tin  mine  in  Cornwall    . 

58.  Vertical  section  of  tiie  Straits  of  Gibraltar 

59.  Irruption  of  the  sea  in  Zealand 

60.  Eruption  of  a  submarine  volcano     . 

61.  Submarine  erupt  on  at  tlie  Azores  . 

62.  Rite  of  a  new  island  near  Ouniraack 

63.  Eruption  of  Tomboro  in  1821 

64.  Paris  covered  by  the  sea 

65.  A  village  buried  under  sand  dunes 

66.  Floating  glaciers 

67.  Telegraphic  cable  nt  the  boltom  of  the  oct  aL 


XIX 

PAU  k 

.  272 

.  276 

.  27J> 

.  28r> 

.  300 

.  303 

.  .309 

.  31ti 

.  32(1 

.  .323 

.  335 

.  374 

.  377 

.  39;^ 


THE  BOTTOM  OF  TIIP]  SEA. 


SUBMARINE  OROGRAPHY. 


1.  The  Plummet — Brooke's  Deep-sea  Sounding  Apparatus. 

In  these  days  of  great  achievement,  when  a  voyage 
rouDd  the  world  has  become  a  lioliday  trip,  the 
youngest  boy  who  is  capable  of  construing  Horace 
may  wonder  that  a  time  ever  existed  when  it  was 
thoiigiit  to  be  an  act  of  impious  daring  to  cross  the 
Ocean.  Nevertheless,  it  may  be  worth  a  moment's 
reflection'  to  realise  the  actual  position  of  a  ship 
which  has  spread  sail  for  some  distant  port,  and 
left  familiar  coasts  far  behind.  What  shall  we 
call  a  vessel  under  these  circumstances?  A  house 
floating  in  mid-ocean,  on  a  shoreless  sea,  with  nothing 
visible  around  but  the  heavens,  overarching  every- 
where the  monotonous  waste  of  waters.  The  ship 
snils    on,  with    tiie    drifting  clouds   above,  and  the 

B 


2  TUE  BOTTOM  OF  THE  SEA. 

currents  of  ocean  below.  By  what  miracle  shall 
the  sailor  be  able  to  keep  on  the  track  to  his  des- 
tined port  ?  By  what  means  shall  he  ascertain  the 
position  he  occupies  on  the  vast  extent  of  ocean? 
The  science  of  astionomy  conies  to  his  help,  fur- 
nishing him  with  the  most  simple  and  exact  pro- 
cesses, by  which  he  may  discover  at  any  moment 
the  route  he  is  following,  and  the  distance  which 
yet  separates  him  from  his  haven.  It  is  by  her 
•lid  that  he  is  able  to  pass  safely  through  dangers 
almost  numberless,  to  avoid  iron-bound  shores  and 
reefs,  against  which  he  would  blindly  hurl  himself 
to  destruction  if  the  stars  did  not  light  his  uncertain 
way. 

But  it  sometimes  happens  that  the  observance 
of  the  heavenly  bodies  fails  the  mariner  at  the  very 
moment  when  he  is  most  in  need  of  their  services. 
Let  us  recall,  for  example,  the  numerous  dangers, 
even  when  the  sea  is  quite  calm,  in  which  the  ship 
is  involved  which  involuntarily  approaches  a  coast 
hidden  from  view  by  a  thick  curtain  of  fog.  In 
this  and  analogous  cases,  the  seaman  resorts  to  other 
means  for  help  than  those  furnished  by  astronomy. 
Among  the  means  most  universally  employed  is  the 
plummet.  It  may  be  that  the  good  ship  is  slowly 
drifting  on  to  a  bank  of  sand  or  gravel  which  would 
be  its  destruction.     The  lead  is  thrown,  and  the  sea 


THE  PLUMMET.  3 

sounded.  In  the  approaches  to  some  coasts  or 
harbours  where  dangerous  rocks  abound,  the  plum- 
met is  indispensa'ile  as  a  means  of  discovering  the 
depth  and  character  of  the  bottom.  Is  it  mud,  or 
sand,  or  gravel,  or  rock  ?  Will  it  be  advisable  to 
cast  anchor,  or  to  find  a  more  favourable  situation? 
The  plummet  will  answer  these  questions. 

In  its  simplest  form  this  little  instrument  con- 
sists of  a  cylinder  of  lead,  suspended  by  a  cord 
attached  to  one  of  its  extremities,  while  the  other  is 
tallowed  in  order  that  some  portion  of  the  soil  at 
the  bottom  of  the  sea  may  adhere  to  it.  It  is 
simply  dropped  into  the  water,  and  allowed  to  fall 
suddenly  to  the  bottom.  The  imperfection  and  un- 
certainty of  such  an  instrument  are  obvious.  If  the 
sea  be  calm  and  of  slight  depth,  it  may  prove  equal 
to  its  work,  and  report  correctly.  But  how  often  is 
the  lead  pulled  up  without  anything  adhering  to  it ! 
The  sea,  in  fact,  is  seldom  or  never  at  rest,  and  at  all 
times  there  are  currents  below  the  surface,  which 
may  carry  away  in  a  bight  hundreds  of  yards  of  the 
line,  without  indicating  that  the  lead  has  reached  the 
bottom. 

Various  attemj)ts  have  been  made  to  improve  the 
plummet.  The  object  has  been  to  make  quite  sure 
that  it  shall  bring  up  to  the  surface  a  sample  of  the 
soil  at  the  bottom  of  the  sea,  and  to  diminish  the 


THE  BOTTOM  OF  THE  SEA. 


effect  of  currents,  so  that  no  error  may  be  occasioned 
by  tbe  length  of  line  carried  away  out  of  the  \)er- 
peiidieubir.     The  most  ingenious  of  tbese  improved 


K:g. 


-l>ionke*s  Det'p- 


tunJiiig  Apparatus. 


contrWances  is  that  invented  by  Passed  Midshipman 
Jo  M.  Brooke,  of  the  United  States  Navy,  who  wixs 
at  the  time  associated   with  the  celebrated  Maury. 


DEEP-SEA  SOUNDING, 


This  clever  coutrivauce,  since  well  known  as  Brooke's 
"  Deejvsea  Sonnfling  Apparatus,"  is  represented  in 
the  annexed  engravings  (figs.  2  &  3).     aa.  is  a  canr.ou- 


Kig.  3. — Striking  the  Seu-lK)ttoni. 

hall,  perforated,  so  that  the  rod  or  cylinder,  bb,  may  he 
passed  throngh  it.  Fig.  2  shows  the  ai)paratns  ready 
for  heinj]:  lowered  into  the  sea.     The  cannon-liall  is 


6  THE  BOTTOM  OF  THE  SEA. 

supported  a  certain  distance  up  the  rod,  on  wliich  i*^ 
slides  freely,  by  means  of  the  sling  dd,  the  ends  of 
which  are  looped  on  to  the  moveable  ears  at  the  top 
of  the  rod.     To  these  also  the  line  is  attached  by 
which  the  apparatus  is  lowered  into  the  ocean.     Thi 
weight  of  the  shot,  being  sufficient  to  resist  a  curreni 
carries  the  line  down  perpendicularly ;  and  when  th« 
protruding  end  of  the  rod  strikes  the  bottom  (fig.  3) 
the  line  slackens,  the  moveable  ends  drop,  and  th« 
loops  of  the  sling  are  disengaged.     The  shot  thej 
slides  down  the  rod,   and  the  latter,  no  longer  en 
cumbered  with  the  weight  a,  can  be  drawn  up  wit) 
ease.     It  will  be  seen  that  a  sort  of  cup  is  formed  a 
the  lower  end  of  the  rod,  and  this  is  "  armed  "  witi 
soap  or  tallow,  so  that   a  specimen  of  the  submarin 
•joil  may  adhere  to  it :    or  the  barrel  of  a  commoi 
quill  is  attached  to  the  rod,  which  is  said  to  answe 
better.     By  either  contrivance  specimens  of  the  sea 
bottom  have  been  brought  up  from  a  depth  of  nearb 
four  miles.     Every  time  this  apparatus  is  used  th( 
shot  and  sling  are  of  course  lost,  the  rod  alone  being 
recovered  when  the  line  is  pulled  in. 

Attempts  to  sound  the  sea  before  the  invention  of 
this  method  have  produced  results  which  are  now 
regarded  as  being  of  little  or  no  value.  The 
honour  of  having  made  the  first  attempt  belongs 
to  Peter  the  Great,   who  constructed  an  apparatus 


DEEP-SEA  SOUS  ding:  7 

\vitli  liooks,  especially  for  the  Caspian.  Others, 
guided  by  theory,  have  devised  petards  which  were 
to  be  exploded,  or  bells  which  were  to  be  rung,  a 
certain  number  of  feut  below  the  surface  of  tlie 
ocean ;  and  it  was  hoped  that  an  echo  would  be  heard 


V\g.  4. — Pleasuring  tlie  Depth  of  the  Sea  by  means  of  a  Bomb. 

from  the  bottom,  the  distance  of  which  could  of 
course  be  calculated.  Experiments  of  this  kind  were 
made  when  the  winds  were  hushed  and  all  was  still ; 
but  echo  was  silent.  M.  de  Tessan  suggested  the 
more  likely  method  of  letting  a  bomb  fall  into  the 


8  TinC  BOTTOM  OF  THE  SEA. 

sea  which  would  explode  when  it  struck  the  bottom. 
The  noise  of  the  report  would  reach  the  surface, 
and  the  time  that  had  elaj^sed  from  the  moment  the 
■  jomb  was  dropped  into  the  water  would  afford  the 
means  of  calculating  the  vertical  distance  it  had 
fallen.  It  is  well  known  that  water  is  a  good  trans- 
mitter of  sound.  Dr.  Colladon  caused  a  clock  to 
strike  under  the  water  of  the  Lake  of  Geneva,  and 
it  was  heard  in  the  first  experiment  four  leagues  oif, 
and  in  the  second  at  more  than  twice  that  distance. 
However,  no  apparatus  has  been  contrived  which 
solves  the  problem  so  thoroughly  as  the  invention  of 
Brooke. 


2.  Construction  of  Charts  and  Sections  of  the  Ocean  Bottom — But 
little  as  yet  known  of  this  subject — Maury,  the  Founder  of 
Submarine  Orographic  Science. 

Let  us  imagine  the  commander  of  a  vessel  sailing 
across  the  ocean  to  be  capable  of  taking  sounrlings  in- 
cessantly from  the  first  to  the  last  moment  of  his  voyage, 
his  apparatus  being  so  contrived  that  the  line  would 
shorten  or  lenfj^then  with  such  exactness,  according  to 
the  varying  depth,  that  the  lead  always  just  touched 
the  bottom.  His  observations,  in  such  a  case,  would 
bear  a  close  resemblance  to  those  which  would  be 
made  by  a  boatman  crossing  a  river  in  the  same 
way.     The  plummet  would  at  first  sink  to  a  certain 


CONSTRUCTION  OF  CHAllTS.  9 

depth,  then  it  would  rise,  then  sink  1on\  er  again  ;  and 
so  go  on  rising  and  falling  at  various  intervals,  until 
the  ship  arrived  at  some  island  i»r  C(jntinent,  when 
the  lead  would,  of  course,  be  once  more  level  with 
the  surface.  If  we  imagine,  further,  that  the  com- 
mander was  careful  to  r;  cord  his  observations  from 
moment  to  moment,  and,  finally,  to  trace  on  a  sheet  of 
paper  the  section  formed  by  the  constantly  varying 
length  of  the  plummet  line,  we  should  see  at  a  glance 
the  exact  configuration  of  the  sea-bottom  throughout 
the  ship's  course  from  one  coast  to  the  other. 

Fig.  5  is  a  vertical  section  of  the  Atlantic,  in  a 
line  from  Mexico,  across  Yucatan,  Cuba,  San  Do- 
mingo, and  the  Cape  de  Verds,  to  Senegambia,  on 
the  African  coast ;  and  it  may  be  regarded  as  the 
result  of  such  a  voyage  as  we  have  imagined.  The 
horizontal  line  represents  the  level  of  the  sea.  Th(3 
irregular  line  which  cuts  it  in  many  points  follows 
the  undulations  of  the  sea  bottom.  Where  it  rises 
above  the  horizontal  line  there  is  land — that  is  to 
say,  the  solid  crust  of  the  earth  is  higher  than  the 
waters.  Where  its  curve  falls  below  the  horizontal 
line,  the  land  is  submarine,  or  under  the  water. 
Thus,  supposing  that  we  take  our  departure  from 
the  Mexican  coast,  the  plummet  descends  at  first 
nearly  2000  feet,  and  leturns  to  the  surface  on  the 
coast  of  Yucatan.     After  doubling  this  peninsula, 


10 


THE  BOTTOM  OF  THE  SEA. 


there  is  again  an  abrupt  descent  of  about  3300  feet ; 
and  from  thence  to  Cuba  the  valley  is  only  inter- 
rupted by  a  chaiu  of  submarine  hills  of  little  im- 
portance. Hounding  Cuba,  we  find  ourselves  floating 
above  a  perpendicular  ravine,  from  7000  to  8000 
feet  deep,  bet\V(  en  that  island  and  Ilayti.     Between 


90" 
« 


80° 
* 


70*^ 


60° 


2(,o 


2000  : 
1000 

xooo  . 

2000 

3000 

fcouo 

(ooo 

CooO. 


<2i  <^ 

o  o 

o  o 

00  o 

(M  CO 


o 


p    — 


t:  .g  .s 


^  ^  ^=S  o  o 

o  o  o  o  §  ^, 

»0  r-l  (M    O    t-    -^ 

l~  t^  ^C)  f,  „  ^ 


o  o  ^ 

o  o  t: 


o  « 


[The  sciile  on  t',e  left  h  md  of  the  diagiam  is  in  metres ;  the 
depths  are  given  in  equivalents  of  feet. \ 

Fig   5. — Vertical  Section  of  the  Atlantic  from  Yucatan  (coast  of  Mexico) 
to  Senegal. 

Hayti  and  Porto  Rico,  and  between  the  latter  and 
the  Windward  Isles,  the  average  r^epth  is  something 
less  than  7000  feet.  Beyond  the  Lesser  Antilles 
there  is  nothing  above  the  waves  until  we  reach  the 
Cape  de  Verd  Islands.  Wlien  we  first  spread  sail 
for  that  point,  the  plummet  falls  suddenly  to  a  dep.h 


FORM  OF  THE  SEA-BOTTOM.  11 

of  16,500  feet  or  more,  and  rises  as  su'ldonly  to  little 
more  than  lt),000  feet.  Again,  it  descends  suddenly 
to  16,000  feet ;  and  then  continues  to  mark  a  depth, 
varying  by  sudden  changes,  say  from  16,000  to 
10,000  feet,  until  near  the  Cape  de  Verd  Islands, 
when  the  depth,  even  clo-e  inshore,  is  about  14,700 
feet.  These  pinnacled  isles  rise  to  the  height  of  10,000 
feet  above  the  surl'ace  of  the  sea.  Deep  gulfs  se- 
parate the  one  from  the  other ;  and  a  still  deeper 
trench  or  canal,  with  almost  perpendicular  sides, 
brings  the  navigator  to  the  African  coast. 

We  have  mentioned  the  uncertainty  of  the  results 
obtained  by  the  plummet  in  ordinary  circumstances ; 
and  from  the  description  we  have  given  of  this  im- 
perfect instrument,  it  will  be  obvious  that  it  affords 
no  means  for  continuous  or  unbroken  observation. 
It  is  necessary  to  make  a  fresh  cast  of  the  lead  each 
time  we  want  to  sound  the  deep.  We  can  only  ob- 
tain, therefore,  a  series  of  points  separated  by  inter- 
vals, whicli  must  be  rendered  as  short  as  possible,  iu 
order  that  they  may  yield  an  approximately  exact 
representation  of  the  sea-bottom. 

In  surveying  any  portion  of  land,  with  a  view 
to  its  exact  delineation,  we  can  generally  move 
freely  over  the  surface  itself  that  we  are  studying. 
The  operations  of  geo'esy  give,  with  the  utmost 
accuracy,  the  positions  and  the  heights  of  as  numy 


12  TRE  BOTTOM  OF  THE  SEA. 

points  as  we  desire.  Suppose,  .however,  that  the 
conditions  of  our  (existence  were  su-h  as  to  maintain 
as  constantly  at  the  height  of  1(3,00 l)  feet  above  the 
sea-level  ?  In  that  case,  our  survey  of  the  land 
would  be  attended  with  the  same  degree  of  difficulty 
as  our  attempts  to  delineate  the  floor  of  the  ocean. 
The  highest  mountains  only  would  11  tt  their  summits 
into  our  atmosphere,  and  those  alone  we  should  be 
able  to  explore  by  the  observation  of  actual  contact. 
The  plummet,  or  some  analogous  instrument,  would 
have  to  be  used  for  ascertaining  the  configuration  of 
the  less  elevated  regions.  This  is  precisely  our  case 
in  regard  to  the  depths  of  the  ocean.  The  regularity 
of  its  surface  enables  us  to  make  use  of  it  as  a  common 
point  of  departure  irom  which  to  measure  the  relative 
heights  of  different  parts  of  the  terrestrial  surfac. 
If  sufficient  water  existed  to  cover  all  the  land,  our 
globe  would  everywhere  present  the  regular  surface 
of  a  sphere,  or  nearly  so.  Although  this  is  not  the 
case,  yet  the  great  oceans,  and  all  the  seas  communi- 
cating with  them,  have  the 'same  level. 

The  pressure  of  the  air  is  pretty  constant  on  every 
point  of  the  ocean-surface,  and  it  is  found  to  diminish 
in  a  certain  ratio  as  we  ascend  in  the  atmosphere. 
It  must  be  remembered  that  the  bottom  of  the  at- 
mospheric ocean  rests  on  the  surface  o.'  the  water v> 
ocean.     If  we  suppose  the  wliole  mass  of  water  to 


PRESSVliE  0±  AIR  AND  WATER.  13 

consist  of  a  certain  number  of  strata,  it  is  obvious 
that  the  lowest  of  these  must  bear  the  weight  of  all 
above  it,  aud  is  therefore  more  compressed  than  the 
next  higher,  and  so  on  till  we  reach  the  surface.  So 
with  the  atmosphere.  Its  entire  weight  presses  on 
the  lowest  stratum  which  touches  the  sea,  aud  that 
weight  of  pressure  in  the  torrid  and  temperate  zones 
is  marked  by  the  barometer  at  30  inches.  If  we 
take  the  barometer  87  feet  above  the  level  of  the 
sea,  it  will  mark  the  diminished  pressure  by  29*9, 
showing  that  it  is  one-tenth  less.  To  show  a  diminu- 
tion of  another  tenth  it  would  be  necessary  to  go 
through  a  second  space  of  more  than  87  feet,  because 
the  pressure  of  the  whole  atmosphere  is  less  by  the 
height  already  attained.  Thus,  we  shall  find  it 
necessary  to  rise  higher  and  higher  for  every  succes- 
sive tenth,  until  we  reach  a  point  when  the  pressure 
altogether  ceases  and  is  marked  by  0.  This  would 
be  at  the  top  of  the  atmosphere. 

The  reader  will  now  understand  how  it  is  that  a 
barometer  serves  to  indicate  the  height  of  any  part  of 
the  earth's  surface;  indeed,  it  is  the  only  possible 
means  at  our  command  in  many  cases  for  ascertaining 
height.  A  process  analogous  to  this  would  be  em- 
ployed with  advantage  to  measure  the  depths  of  the 
sea.  Suppose  an  instrument  to  be  sunk  in  the  water. 
The  depth   of  water  through  which  it  had   fallen 


14  THE  BOTTOM  OF  THE  SEA. 

adding  its  pressure  to  that  of  the  superincumbeni 
air,  and  water  being  estimated  at  1300  times  the 
weight  of  air,  it  is  plain  that  calculations  which  have 
been  made  relative  to  the  atmosphere  would,  a 
fortiori,  seem  to  be  possible  also  relative  to  the  ocean. 
An  instrument  so  constructed  as  to  indicate  the 
pressure  to  which  it  had  been  subjected  in  the  water 
would  serve  to  complete  or  correct  the  results  given 
by  the  sounding  apparatus.  Discordant  indications 
would  possibly  afford  evidence  as  to  the  direction  and 
force  of  submarine  currents. 

If  we  add  to  the  imperfection  of  the  processes 
themselves  the  difficulties  of  an  accidental  character 
which  attend  their  application,  we  shall  find  but 
little  reason  for  wonder  that  submarine  orography  is 
so  little  advanced.  To  make  deep-sea  soundings,  a 
ship  must  be  provided  with  a  considerable  amount  of 
materiel  of  no  use  for  any  other  purpose.  A  single 
operation  during  a  voyage  must  employ  several  per- 
sons, and  it  could  only  be  made  in  fair  weather.  In 
general,  therefore,  merchant-ships  cannot  be  provided 
with  instruments  and  with  hands  to  make  deep-sea 
soundings;  they  would  require  cables  or  lines  some 
four  miles  in  length,  and  their  crews  would  seldom  be 
strong  enough  to  deal  with  such  heavy  tackle.  ^Fhen, 
the  time  spent  in  such  operations  would  occasion  incal- 
culable loss  to  merchants  and  ov/ners ;  and  if  the 


HESULTS  OF  EXPERIMENTS.  15 

c^ble  parted,  that  expense  would  be  added  to  the  rest, 
and  thus  the  lost  apparatus  could  seldom  be  replaced. 
Evidently,  experiments  of  this  kind  can  only  be  made 
by  Governments,  or  by  commercial  companies  in- 
terested in  their  results.  For  example,  the  laying  of 
submarine  telegraph  cables  has  made  it  necessary  in 
recent  times  to  sound  the  ocean  in  various  tracks. 
Almost  every  day  sees  some  addition  made  to  our 
knowledge  in  this  way,  and  there  can  be  no  doubt 
that  the  multiplication  of  submarine  telegraph  lines 
will  tend  very  greatly  to  hasten  the  time  when  we 
shall  have  an  accurate  idea  of  the  form  of  the  earth, 
and  of  the  lesser  accidents  which,  affect  its  surface. 

Before  the  general  form  of  the  earth  was  ascer- 
tained, the  depths  of  the  ocean  were  the  subject  of 
the  most  extravagant  suppositions.  The  writings  of 
geographers  abound  in  such  expressions  as  that  of 
"  a  bottomless  and  shoreless  sea,"  to  designate  the 
Atlantic  Ocean.  The  abandonment  of  such  absurdi- 
ties is  a  necessaiy  consequence  of  the  facts  known  in 
the  present  day  concerning  the  form  and  physical 
constitution  of  our  planet.  But  other  speculations, 
not  less  calculated  to  fill  the  imagination  with  an 
idea  of  grandeur,  have  taken  their  place.  If  the  mass 
of  water  which  covers  about  three-fourths  of  the  solid 
crust  of  the  globe  is,  after  all,  limited  in  quantity, 
what  is  the  depth  of  the  basins  which  contain  it  ? 


16  THE  BOTTOM  OF  THE  8Ea 

The  terrestrial  shell  is  known  to  be  irregularly 
broken,  and  its  fragments,  so  to  speak,  piled  on  one 
another  in  gigantic  masses  of  picturesque  confusion — 
here  heaved  up  into  the  air,  there  sunk  from  depth 
to  depth,  with  the  waters  of  ocean  gathered  in  their 
deepest  gulfs.  Plainly,  if  we  add  to  the  measurement 
of  these  depths  beneath  the  sea  that  of  the  heights 
above,  we  shall  obtain  some  useful  data,  and  be 
enabled  to  form  an  approximate  estimate  of  the 
stupendous  forces  in  the  interior  of  the  globe 
which  have  produced  such  irregularities  on  its 
surface. 

Before  Maury  made  his  appeal  to  the  marine  of 
all  nations,  something  was  known  of  the  sea-bottom 
in  the  vicinity  of  coasts,  and  in  the  most  frequented 
tracts ;  but  very  little  was  apprehended  of  what  lay 
under  blue  water.  He  called  upon  his  brother  sailors 
to  commence  a  systematic  observation  of  the  winds 
and  of  meteoric  phenomena,  to  note  the  marine  cur- 
rents, and  to  sound  the  sea  as  they  traversed  it,  if 
possible,  every  hundre  1  leagues.  His  call  was  heard, 
and  heartily  responded  to.  In  a  few  years  the  North 
Atlantic,  ploughed  by  the  ships  of  all  nations,  had 
been  sounded  in  so  many  points,  that  Maury  was  able, 
by  combining  the  results  obtained,  to  trace  the  con- 
fiouration  of  the  bottom  of  that  ocean,  and  construct 
a  chart  analogous  to  a  geographical  tracing  designed 


nEPTH  OF  BLUE  WA  TER.  17 

to  indicate  the  surface  of  a  country  in  relief.  The 
curves  are  so  drawn  and  stippled  as  to  show  distinctly 
when  the  water  is  less  than  6000  feet  deep,  when  it 
is  less  than  12,000  feet  deep,  when  it  is  less  than 
1«,000  feet,  and  when  its  depth  lies  between  that  and 
24,000  feet.  The  conclusion  is  that  the  average 
depth  of  blue  water  is  not  more  than  three  or  four 
miles,  and  that  no  reliable  soundings  have  been 
made  in  water  over  five  miles  deep.  This  map  (a 
reduced  copy  of  which  is  given  opposite  p.  28)  gives 
an  idea,  though  an  imperfect  one,  of  tlie  configura- 
tion of  the  floor  of  the  North  Atlantic  Ocean. 

The  Mediterranean,  the  Black  Sea,  the  Baltic,  and 
the  seaboards  of  France  and  the  British  Isles,  are 
much  better  known.  These  seas  are  shallow  com- 
pared with  the  ocean,  and  the  European  marine 
has  too  great  an  interest  in  their  study  to  neglect 
them. 

On  the  other  hand,  in  the  immense  spaces  left  in  the 
southern  hemisphere  by  the  continents  and  islands  of 
Oceania  the  lead  has  rarely  been  thrown.  The  deep- 
sea  basins  which  separate  Asia  and  Africa  from 
Australia  and  America  have  been  but  slightly  ex- 
plored, chiefly  because  tlie  navigator  there  sails  fear- 
lessly before  the  wind,  and  dreads  no  rock  or  shoal 
which  would  make  him  desirous  of  knowing  the 
depth  of  water  on  which  he  floats.     Some  observa- 

c 


18  THE  BOTTOM  OF  THE  SEA. 

tions  have  been  made  by  tlie  scientific  voyages  of 
observation  sent  out  at  the  expense  of  States ;  but 
except  these  we  know  of  none  that  are  available. 

T!ie  southern  part  of  the  Athmtic  Ocean  is  equally 
a  blank ;  and  to  make  a  sum  of  the  whole  matter, 
the  greater  part  of  the  wcrld  beneath  the  sea  is  in- 
differently known.  If  we  add  to  this  fact,  that  the 
greater  part  of  continents  is  desert  or  savage,  traversed 
occasionally  by  a  few  hardy  adventurers,  we  shall 
begin  to  see  how  vast  are  the  lacunae  still  remaining 
in  our  study  of  the  globe,  and  what  an  ample  harvest 
of  discovery  may  yet  be  reaped  by  the  conscientious 
observers  of  nature. 

3.  Analogy  between  the  Configuration  of  Continents,  and  that  of 
the  Bottom  of  the  Sea — Equatorial  Section  of  the  Earth. 

Although  the  scientific  results  which  we  have  al- 
ready mentioned  are  incomplete,  they  are  sufficient  to 
prove  that  the  greatest  depth  of  the  sea  does  not  ex- 
ceed about  five  miles ;  thus,  that  it  is  about  equal  to 
the  height  of  the  loftiest  mountains.  This  depth 
has  been  plummed  in  all  the  great  oceans,  and  occa- 
sionally deeper  soundings  have  been  reported.  The 
results,  however,  in  the  latter  case  have  been  obtained 
under  circumstances  which  do  not  command  our 
confidence.  Such  are  the  cases  in  which  it  would  be 
eminently  satisfactory  to  employ  an  instrument  to 


SUBMARINE  SCENERY.  19 

indicate  the  depth  by  pressure,  as  suggested  in  the 
foregoing  section. 

The  submarine  soil  in  its  configurations  bears  n 
close  resemblance  to  tlie  subaerial  surfece.  The  geo- 
graphical accidents,  so  to  speak,  are  the  same.  There 
are  plains,  valleys,  ravines,  hills,  escarpments,  deserts 
of  sand,  immense  deposits  of  mud,  rolled  stones,  pic- 
turesque rocks,  and  even  water-springs  and  vol- 
canoes. 

But  while  the  bones  of  the  earth  beneath  the 
waters,  or  the  framework  of  the  picture,  so  closely 
resembles  that  of  the  soil  above,  the  picture  itself 
presents  a  very  different  aspect  to  the  observer.  In 
the  first  place,  there  is  but  scant  light  a  little  distance 
below  the  surface ;  then,  the  vegetation  is  of  a  totally 
different  character :  the  various  al^rae  float  their  long: 
and  brilliantly-coloured  ribbons  in  the  most  graceful 
curves  and  modulations,  or  display  their  elegant 
tracery  in  fine  and  clearly-cut  relief,  like  our 
mountain-trees.  Animals,  strange  to  our  eyes,  move 
slowly  in  an  element  which  may  be  called  gross  when 
compared  with  our  atmosphere.  Springs  of  fresh 
water,  instead  of  running  upon  the  soil,  are  dispersed 
in  vapour ;  volcanic  eruptions  assume  a  peculiar 
character.  Yet,  with  all  these  differences,  the  basin 
of  the  sea,  in  the  eyes  of  the  geometer,  is  in  all 
essential  respects  similsj  to  its  shores. 


20  THE  BOTTOM  OF  THE  SEA. 

Let  US  suppose  the  sea  to  be  suddenly  withdrawn 
from  its  basin,  in  order  that  we  may  the  more  clearly 
apprehend  the  conformation  of  the  terrestrial  crust  as 
a  whole,  and  thus  see  at  a  glance  the  unequal  heights 
and  depths  which  appear  to  us  so  considerable,  but 
which,  in  reality,  are  very  small  when  compared  with 
the  vast  bulk  of  the  planet:  Let  us,  in  short,  sup- 
pose the  earth  to  be  reduced  to  the  same  physical 
condition  as  the  moon,  without  an  atmosphere  and 
without  water  :*  the  eye  would  be  arrested  by  vast 
ramparts  formed  of  the  earth's  upheaved  strata,  and 
piled  to  a  total  height  of  some  ten  or  eleven  miles — 
the  most  gigantic  of  these  picturesque  eminences 
corresponding  to  the  Old  World,  and  having  its 
culminating-point  in  the  Himalayas.  All  around 
that  vast  rocky  barrier  would  be  seen  a  deep  furrow 
separating  it  from  the  double  gibbosity  formed 
by  the  two  Americas ;  and  taking  our  stand  on  the 
southern  extremity  of  the  latter  continent,  we  should 
descry  in  the  distance  the  summits  of  Australia 
and  the  neighbouring  isles,  and  the  ramparts  of 
the  great  Austral  continent,  almost  entirely  buried 
under  snow  and  ice. 

As  the  continents  have  their  highest  summits,  so 
the  oceans  have  their  deepest  gulfs,  and  these  are  often 

*  Speaking  from  present  appearances ;  for,  in  fact,  this  point  is 
not  yet  placed  absolutely  beyond  doubt. — Tn. 


8UBMA  JtlNE  SCENER  Y  2 1 

near  neighbours  to  each  other.  The  Himalayan 
peaks  are  not  far  from  the  deepest  part  of  the  iLdian 
Ocean ;  the  Eocky  Mountains  have  for  their  near 
neighbour  the  deep  gulf  of  the  Northern  Pacific; 
the  Alleghanies  are  contiguous  to  the  lowest  depths 
of  the  North  Atlantic ;  and  the  towering  bulk  of  Mont 
Blanc  may  be  said  to  rise  out  of  the  deepest  part  of 
the  westerf  Mediterranean  basin.  This  remark  is  of 
general  application,  and  we  may  add,  that  if  on  any 
coast  the  highest  point  of  the  upheaved  surface  almost 
equals  the  depth  of  the  depression,  that  of  the  op- 
posite coast  will  be  as  far  removed  from  it;  as  if 
the  doublings  and  upliftings  to  which  the  actual 
configuration  of  the  earth's  crust  is  due  were 
unsym metrical,  and  had  produced  on  the  one  coast 
a  gentle  declivity,  on  the  other  a  steep  hill. 

On  the  subaerial  part  of  the  earth  there  are  vast 
plateaux  or  table-lands,  and  elevations  of  considerable 
altitude.  Submarine  plateaux  are  in  like  manner 
of  frequent  occurrence;  they  separate  two  basins, 
the  rocky  edges  of  which  are  not  sufficiently  high  to 
appear  above  the  waters.  In  the  Northern  Atlantic 
Ocean,  for  example,  a  vast  plateau  stretches  from 
Iceland  to  the  Azores,  and  thence,  southward  and 
westward,  to  the  Antilles  or  West  Indies.  The  Azores 
correspond  to  volcanic  peaks,  rising  from  that  chain 
o^'  submarine  mountains.     Another  plateau  extends 


22  THE  BOTTOM  OF  THE  8EA. 

to  the  north,  the  east,  and  a  little  to  the  south  of 
Newfoundland,  terminating  abruptly  about  the  lati- 
tude of  New  York  in  a  steep  shore,  along  the  escarp- 
jnent  of  which  flows  the  celebrated  Gulf  Stream.  Near 
it,  the  orographic  chart  shows  the  centre  of  a  basin 
where  the  sea  is  about  five  miles  deep,  compared  with 
less  than  a  third  of  that  depth  on  the  plateau.  The 
now  familiar  Telegraphic  Plateau  is  thp  latest  dis- 
covery of  this  kind.  It  is  a  remarKauie  steppe,  ex- 
tending from  Cape  Clear  in  Ireland  to  Cape  Kace  in 
Newfoundland,  and  upon  it  the  mystic  chain  which 
unites  the  intelligence  of  the  Old  and  the  New  World 
reposes  in  perfect  security. 

Sometimes  from  the  submarine  plateau  there  spring 
numerous  mountain-peaks,  which  lift  their  heads 
above  the  ocean,  and  rise  to  a  considerable  height  in 
the  atmosphere.  Thus,  an  archipelago  or  cluster  of 
islands  consists  of  the  culminating-points  of  mountain- 
chains,  the  bases  of  which  are  planted  on  submerged 
plains.  If  the  Americas  were  covered  with  water  to 
the  depth  of  a  mile,  more  or  less,  we  should  find  in  their 
places  groups  of  islands  corresponding  to  the  Rocky 
Mountains,  the  Andes,  the  Brazilian  Mountains,  and 
to  some  peaks  of  the  Alleghanies  and  Antilles.  The 
plummet  would  indicate  the  existence  beneath  the 
waters  of  great  valleys  separated  by  hills,  by  plateaux, 
or  by  mountains,  for  the  most  part  with  easy  declivities ; 


ROUNDNESS  OF  THE  SEA-BOTTOM.  23 

but  more  abrupt  near  the  present  sliores  of  the  con- 
tinent, especially  on  the  western  side,  which  overlooks 
the  great  ocean. 

The  bed  of  the  sea  cannot,  with  strict  accuracy,  be 
compared  to  the  bed  of  a  river.  A  section  of  the 
Mississippi,  at  Plaquemines  for  example,  resembles  a 
gutter.  Neither  does  a  lake  of  small  extent  present 
the  means  of  a  satisfactory  comparison,  however  deep 
it  may  be.  If  we  join  the  two  opposite  shores  of  a  lake 
by  a  straight  line,  that  line  will  be  above  the  bottom  of 
the  lake,  and  will  thus  appear  as  a  portion  of  the 
surface.  This  is  not  true  of  a  sea,  if  it  be  of  any  con- 
siderable size.  The  earth  IS  roun4ed  in  form,  the 
free  surface  of  the  ocean  is  almost  perfectly  spherical; 
and  it  is  from  that  surface,  as  a  starting-point,  that 
the  depth  of  the  sea  must  be  estimated.  Drive  a 
rectilinear  tunnel  through  the  earth  from  Paris  to 
Newfoundland,  as  sketched  in  the  annexed  diagram, 


Fig.  6. — Section  of  the  Atlantic  Ocean  fVom  Paris  to  .Ww  uminilaud. 

and  it  will  be  found  that  this  tunnel  nowhere  encoun- 
ters the  ocean.     It  will,  in  fact,  pass  far  beneath  it. 


24  TBE  BOTTOM  OF  THE  SEA. 

Its  entrance  in  Paris  will  neither  be  vertical  nor 
horizontal.  It  will  at  once  pass  at  a  considerable  depth 
under  the  English  Channel  and  the  ocean,  notwith- 
standing the  comparatively  great  depth  of  the  latter, 
and  will  reach  the  surface  at  Newfoundland  obliquely 
as  it  had  quitted  Paris  The  same  observation  appliep 
to  all  the  great  seas.  The  form  of  the  earth  being 
spherical,  the  bottom  of  the  ocean,  so  far  from  being 
a  cavity,  is  in  its  general  outline  convex. 

In  order  to  give  the  reader  an  exact  idea  of  the 
relative  thickness  of  the  solid  crust  of  the  earth,  of 
its  liquid  covering,  and  of  its  gaseous  atmosphere, 
we  cannot  do  better  than  draw  a  section  of  the 
equator  (fig.  7).  In  the  centre,  marked  by  the 
diagonal  shading,  is  incandescent  fire,  of  the  charac- 
ter of  which  we  can  only  form  a  conception  from 
the  productions  of  volcanic  eruptions.  A  solid  crust 
of  comparatively  slight  thickness  envelopes  the  fluid 
kernel,  and  rests  upon  it  like  a  raft  upon  the  waves. 
When  that  internal  sea  of  fire  is  agitated,  its  pal- 
pitations are  revealed  to  us  by  startling  results — in  a 
word,  by  the  breaking-up  of  that  fragile  crust  upon 
which  repose  all  our  hopes. 

This  solid  covering  is  enveloped  by  a  double  at- 
mosphere. The  lower  (or  aqueous)  portion  is  not 
adapted  to  our  mode  of  existence ;  we  can  but  float 
upon  its  surface.     It  is  divided  or  broken  up  by  the 


EQUATORIAL  SECTION. 


25 


elevation   of  the  earth  into  the  higher  or  gaseous 
portion,  which  is  alone  appropriate  to  our  nature. 


<r 


1^  "^ 


[77te  scale  of  drptlis  is  fifty  times  greater  than  that  o/leiigihs.] 
F.'g.  7.— Eqiiato;ial  Sectioa  of  the  Earth. 

In    all    prolability   the  thickness  of  the    earth's 


26  THE  BOTTOM  OF  THE  SEA. 

crust  is  very  far  from  being  uniform.  Its  maximum 
cannot  exceed,  even  if  it  reaches,  sixty  miles,  or  less 
than  the  sixtieth  part  of  the  earth's  radius.  In  some 
places  it  is  certainly  very  much  less.  In  the  neigh- 
bourhood of  volcanoes,  for  example,  it  is  so  thin  that 
combustible  matters  are  ejected  through  the  fissures 
in  which  these  mountains  abound. 

The  greatest  depth  of  the  liquid  envelope  is 
probably  less  than  six  miles,  and  the  gaseous  at- 
mosphere, so  far  as  it  is  respirable,  can  hardly  be 
said  to  reach  five  miles  in  height.  It  is  in  this 
limited  zone,  of  ten  or  twelve  miles'  thickness,  that  all 
the  phenomena  of  life  take  place.  How  small  is  this 
space  compared  with  the  great  mass  of  the  globe ; 
and,  to  follow  out  the  contrast,  what  an  atom  is  man 
compared  with  the  immensity  of  the  universe ! 

In  the  section  (fig.  7)  the  bed  of  the  great  Equi- 
noctial Ocean,  and  that  of  the  Indian  Ocean,  is 
marked  by  a  dotted  line,  the  data  being  insufficient 
to  determine  their  depths  with  precision.  This  sec- 
tion cuts  the  northern  part  of  South  America,  and 
touches  the  Pichincha  volcano.  It  asses  by  the 
Galapagos  Islands,  which  are  separated  from  the 
continent  by  a  deep  arm  of  the  sea.  Traversing 
the  middle  of  the  Pacific  Ocean,  it  cuts  the  archi- 
pelago of  the  Scarborough  Isles ;  and,  farther  on,  the 
Moluccas,  the  island  of  Borneo ;  Sumatra,  with  one 


MAUltTS  CEART.  9.1 

of  its  volcanoes ;  Mount  Oi)liir,  directly  opposite 
Picbincha — then  the  Indian  Ocean,  the  immense 
plateau  of  Africa,  the  isle  of  St.  Thomas,  and  the 
Atlantic.  In  making  this  circuit,  we  are  chiefly  im- 
pressed by  the  fact  that  the  external  surface  of  the 
earth's  crust  is  almost  exactly  represented  by  a 
circle.  It  is  not  without  difficulty  that  we  represent 
only  a  slightly  undulating  line,  the  inequalities 
being  exaggerated  in  order  that  they  may  be  at  all 
perceptible. 


4.  Northern  Atlantic  Ocean — Chart  of  Maury. 

• 

The  Atlantic  Ocean  takes  the  form  of  a  great  canal, 
stretching  directly  from  north  to  south,  and  trending 
to  the  east  in  its  northern  part.  With  Maury's  Chart 
before  us  we  shall  find  it  comparatively  easy  to  form 
an  idea  of  the  configuration  of  this  ocean-bed. 

The  curves  which  indicate  its  varying  level  are 
drawn  at  such  a  distance  from  each  other  as  to  mark 
a  thousand  fathoms'  difference  in  the  relative  depths. 
Thus  all  the  points  situated  between  the  shores  and 
the  first  curve  vary  in  depth  from  0  to  1000  fathoms, 
or  GOOO  feet ;  all  the  points  between  the  first  curve 
and  the  second  augment  in  depth  from  1000  to  2000 
fathoms;  those  between  the  second  and  third  from 
2000  to  3000  fathoms ;  and  those  between  \h&  thia-d 


28  THE  BOTTOM  OF  THE  SEA. 

and  fourth  from  3000  to  4000  fathoms.  Any  greater 
depth  is  indicated  by  the  blanks.  On  referring  to 
the  chart  (fig.  8),  it  will  be  seen  that  a  depth  ex- 
ceeding 4000  fathoms  is  thus  marked  between  New- 
foundland and  the  Bermuda  Islands,  in  the  track  of 
the  Gulf  Stream.  The  plummet  there  descends  to 
a  depth  of  about  5000  fathoms,  or  nearly  30,000  feet. 
Westward  of  the  Canary  Islands  is  another  deep  point, 
the  indication  of  the  plummet  being  about  24,300  feet. 

A  marked  region  of  this  ocean-bed,  having  a  depth 
which  varies  from  about  3000  to  4000  fathoms,  ex- 
tendi s  from  the  south  of  Newfoundland,  rounds  the 
Bermudas,  and  follows  very  nearly  the  direction  of 
the  American  coast  to  the  extreme  latitude  of  Florida. 
It  then  winds  south-east,  keeping  a  certain  distance 
from  the  Antilles,  and  terminating  near  the  north- 
eastern extremity  of  that  archipelago. 

A  second  remarkable  trough,  separated  from  the 
last-mentioned  by  a  submarine  chain  of  mountains, 
extends  like  a  long  gutter  from  the  north-west  to  the 
south-east,  even  beyond  the  equator.  It  is  nearer  to 
the  Brazilian  than  to  the  African  coast. 

Throughout  these  regions,  which  are  the  deepest  in 
the  Atlantic  Ocean,  the  bottom  exhibits  great  irregu- 
larity. The  gulf  deepens  rapidly  from  the  coast  of 
America  and  the  Antilles,  but  slopes  gently  from 
Europe  and  Africa.     We  observe,  in  fact,  that  the 


BOTTOM  OF  THE  ATLANTIC.  29 

curves  of  the  chart  approach  very  near  to  each  other 
on  the  west,  and  are  farthest  from  each  other  on  the 
east  of  the  depression.  Another  noticeable  feature  is 
the  immense  plateau  ranging  almost  parallel  with 
the  European  and  African  coast,  and  dividing  what  may- 
be called  the  shelving  side  of  the  ocean-gulf  into  two 
parts,  for  which  reason  it  has  been  named  by  Maur}' 
the  "Middle  Ground."  It  commences  at  Iceland, 
passes  the  Azores,  and  extends  southward  to  the  lati- 
tude of  the  Canary  Islands  ;  then  trends  towards  the 
Bermudas,  and  bulges  southward  to  a  point  east  of 
the  Antilles.  The  depth  of  the  sea  at  the  southern 
termination  of  tliis  plateau  is  marked  in  the  chart  by 
a  curve,  which  indicates  less  than  2000  fathoms,  or 
from  11,000  to  12,000  feet.  This  locality  is  identical 
with  a  part  of  the  Grassy  Sea.  Between  this  middle 
ground  and  the  coast  of  Europe  a  long  valley  extends 
north  and  south,  and,  at  the  Cape  de  Verd  Islands, 
joins  the  depression  which  is  bounded  by  Africa, 
America,  and  the  plateau  or  middle-ground  just 
described. 

The  depth  of  this  valley  is  almost  everywhere  a 
little  under  3000  fathoms,  the  exception  being  another 
spot,  previously  alluded  to,  west  of  the  Canary  Islands. 
In  the  northern  end,  westward  from  the  British  Isles, 
and  even  across  the  Middle  Ground  to  Newfoundland, 
the  depth  is  so  uniform,  that  when  soundings  were 


30  THE  BOTTOM  OF  THE  SEA. 

made  for  the  purpose  of  laying  a  telegraphic  cable 
between  the  Old  World  and  the  New,  all  this  part  of 
the  ocean-bottom  seemed  as  if  it  were  purposely  de- 
signed to  form  the  bed  of  that  wonderful  conductor  of 
thought.  Hence  the  name  of  "  Telegraphic  Plateau  " 
was  given  to  it. 

For  a  considerable  distance  around  the  Azores  the 
depth  is  less  than  1000  fathoms.  About  halfway 
between  the  Azores  and  Newfoundland,  there  is  also 
a  circumscribed  region  of  comparatively  slight  deptli 
— being  marked  in  Maury's  Chart  as  less  than  2000 
fathoms.  In  the  whole  of  this  route — that  is  to  say, 
from  Spain  to  the  Azores,  and  from  the  Azores  to 
Newfoundland — the  depth  nowhere  exceeds  3000 
fathoms.  It  has  therefore  appeared  to  present  a 
suitable  course  for  a  telegraphic  cable.  The  French 
line  is  laid  midway  between  this  plateau  and  the 
English  cable  of  1866. 

Along  the  coasts  of  Brazil  and  Guiana  the  sea  be- 
comes rapidly  shallower ;  and  as  the  great  equatorial 
current  w^hich  carries  .the  waters  from  east  to  west  is 
of  vast  breadth,  we  need  not  feel,  surprised  to  observe 
that  it  increases  in  swiftness  as  it  approaches  the 
coasts  which  confine  its  bed.  There  is  then  a  descent 
or  lower  depth  of  the  sea-bottom  extending  eastward 
from  the  Isthmus  of  Panama  to  St.  Domingo,  as  if  the 
rush  of  the  current  had  washed  out  a  gulf.     This 


B0TTGER8  CHART.  31 

is  succeed ed  by  the  comparatively  shallow  space  of 
the  Gulf  of  Mexico,  and  the  sea  in  the  neighbourhood 
of  the  Greater  Antilles  and  the  United  States. 

A  great  extent  of  shallow  sea  is  also  to  be  observed 
extending  from  Nova  Scotia  to  the  east  of  the  Great 
Bank  of  Newfoundland,  and  to  the  coast  of  Labrador. 
It  is  by  this  route,  as  all  know,  that  the  polar  ice 
and  icebergs  descend  towards  the  Gulf  Stream,  the 
warm  current  of  which  causes  them  to  melt,  and  de- 
posit in  the  bed  of  the  sea  the  debris  of  the  land  from 
which  they  had  drifted  away. 


5.  Tlie  INIediterranean  and  the  Black  Seas — Chart  of  BotJger. 

The  Mediterranean  and  the  Black  Seas  are  of  no 
great  depth.  The  plummet  seldom  reaches  12,000 
feet,  and  not  more  than  half  that  depth  in  the  greater 
part  of  their  extent.  The  waters  of  the  Mediter- 
ranean, however,  cover  many  great  valleys.  The 
deepest  is  surrounded  by  the  shores  of  Tripoli,  Greece, 
and  Italy.  It  is  separated  by  a  narrow  chain  of 
mountains  from  another  great  valley,  which  occupies 
the  space  bounded  by  the  Grecian  Archipelago,  Asia 
Minor  and  the  coasts  of  Syria  and  Egypt. 

Beginning  at  the  Straits  of  Gibraltar,  we  find  the 
submarine  soil  highest  near  the  coasts  of  Spain  and 
Morocco.     At  the  western  end  of  the  strait,  the  depMi 


62  THE  BOTTOM  OF  THE  SEA. 

does  not  exceed  1000  or  1200  feet.  As  we  advance 
eastward  the  depth  augments  rapidly,  till  it  reaches 
nearly  12,000  feet  south-east  of  Malaga.  Soon,  how- 
ever, the  soil  rises  again.  North  of  Melilla  (a  port  on 
the  coast  of  Morocco)  it  is  about  1200  feet  from  the 
level  of  the  sea,  and  forms  a  submarine  mountain- 
chain,  which  bounds  on  the  east  a  sort  of  little  basin 
confined  between  the  Sierra  Nevada  and  the  Marocco 
mountains,  which  are  reunited  under  the  sea  in  the 
Straits  of  Gibraltar. 

Continuing  eastward,  the  explorer  would  descend 
into  another  valley  almost  as  deep  as  that  mentioned 
above,  and  communicating  with  that  great  depression 
by  a  neck  of  the  chain  which  stretches  under  the 
waters  from  Oran  to  the  Cape  of  Gades.  Having 
surmounted  this  obstacle,  we  bend  our  steps  north- 
east, and  find  ourselves  in  a  great  depression,  which  is 
narrow  at  first,  but  gradually  spreading  out  becomes 
a  great  plain  stretching  to  the  Balearic  Isles  and  the 
coasts  of  Sardinia  and  Algeria.  We  leave  this  great 
depression  or  basin  by  climbing  a  very  steep  ascent  to 
the  north-west.  We  then  find  ourselves  upon  an  ex- 
tended plateau,  from  which  rise  numerous  mountain- 
peaks.  The  principal  of  these  form  the  Balearic 
Isles.  The  plateau  is  scarcely  interrupted  by  Cartha- 
gena  and  Valencia,  by  the  Balearic  Isles,  and  by 
Corsica.     It  narrows,  however,  between  these  islands. 


THE  MEDITERRANEAN  BASINS.  35 

and  we  discover  to  the  north  another  irregular  cavity 
occupying  the  space  comprised  between  Majorca  and 
the  coast  of  Spain,  and  the  Gulfs  of  Lyons  and  Genoa. 
The  depth  of  the  sea  there  does  not  exceed  6000  feet; 
and  from  this  bottom  there  rises  an  isolated  peak  at 
the  entrance  of  the  Gulf  of  Lyons. 

To  ascend  from  the  Algerian  depression  eastward, 
it  would  be  necessary  to  avoid  the  escarpments 
around  Sardinia,  and  draw  towards  Tunis,  in  order  to 
find  an  easier  declivity.  All  around  Sardinia  and 
Corsica  the  depth  of  the  sea  is  slight ;  the  basin 
formed  by  the  Tyrrhenian  Sea  has  nothing  to  boast 
of  but  two  straight  and  elongated  ravines — the  one 
extending  from  west  to  east,  rounding  the  Lipari 
Islands  ;  the  other  from  north-west  to  south-east, 
running  parallel  to  the  Neapolitan  coasts. 

The  Bank  Aventure  and  the  Rocks  of  Skerki,  near 
Tunis  and  Sicily,  form  an  undulating  plateau,  over 
which  we  pass  to  the  eastern  basin  of  the  Mediterra- 
nean. A  steep  descent  leads  from  Malta,  one  of  the 
culminating-points  of  the  plateau,  to  the  bottom  of 
the  depression  which  has  for  its  boundaries  Italy  and 
Greece,  Asiatic  Turkey  and  Africa.  The  greatest 
depth  is  near  Malta,  where  the  plummet  descends 
more  than  14,000  f(?et,  or  about  2^  miles.  No  other 
spot  in  the  Mediterranean  is  so  deep  as  this. 

The  mountains  of  Greece  and  Candia  are  prolonged 


36  TEE  BOTTOM  OF  TEE  SEA. 

beneath  the  waters,  and  they  divide  into  two  nearly- 
equal  parts  the  great  cavity  we  are  now  considering. 
1'he  western  part  presents  some  steep  slopes,  but 
generally  the  bottom  rises  very  gradually,  till  we  come 
to  the  shallow  waters  of  the  coast  of  Africa  on  the 
one  hand,  and  to  those  of  the  Adriatic  on  the  other. 


o        '-'        o        o        -s*^        o""o'^o'**''~" 
O         <U        o         o         go        ooo*'ooo 

Cl  H  rH  rH  C/2'<*  r->   (Ji      CO  r^  C^      '~0         'Jl^ 


l^Scale  of  depths  a  hundred  times  that  of  the  length.'] 
Fig.  10. — Depths  of  the  Adiiatic. 

In  this  sea,  if  we  except  a  little  basin  about  4000  feet 
deep,  the  plummet  rarely  if  ever  descends  more  than 
GOO  feet.  The  eastern  half,  or  Graeco-P^gyptian  basin, 
extends  to  the  southern  part  of  the  Archipelago,  as 
far  as  the  coasts  of  Greece.  The  islands  of  Candia, 
Caxo,  Scarpanto,  Khodes,  and  Cyprus  are  planted 
on  its  borders.  The  alluvial  deposits  of  the  Kile 
tend  to  raise  the  level  southward,  as  indicated  by  the 
map.  The  lines,  which  mark  a  depth  not  exceeding 
300  feet,  form  a  spacious  area  in  front  of  the  Delta, 
and  are  succeeded  by  the  curves  of  600  feet,  then  by 
those  of  1500  feet,  and  so  on  to  the  greatest  depth  of 


THE  NORTHERN  SEAS.  87 

the  basin,  about  10,000  feet.  The  course  of  the  marine 
currents  near  the  mouths  of  the  Nile  is  from  west  to 
east.  The  action  of  these  currents,  it  is  hardly  neces- 
sary to  say,  tends  to  carry  the  alluvial  matter  east- 
ward ;  hence  the  deep  part  of  the  sea  is  farther  from 
the  coast  eastward  from  the  Nile  than  westward. 

If  we  ascend  from  this  basin  to  the  north-west,  we 
shall  find  ourselves  among  the  rocky  gorges  domi- 
nated by  Candia  and  Searpanto.  These  irregular  and 
broken  elevations  form  a  great  volcanic  region,  the 
principal  peaks  of  which  form  the  islands  of  the  Greek 
Archipelago. 

The  defiles  of  the  Dardanelles,  the  valley  covered 
by  the  Sea  of  Marmora,  and  the  ravine  commanded 
by  Constantinople  and  Scutari,  open  to  the  plain  upon 
which  debouch  the  greatest  rivers  of  Europe.  The 
Black  Sea  is  of  little  depth.  It  is  surrounded  on  its 
southern  shores  by  the  heights  of  the  Caucasus,  the 
Armenian  mountains,  and  the  Balkan.  Northward 
the  Russian  steppes  extend  imder  the  sea,  which  their 
debris,  waslied  down  by  the  great  rivers,  tend  to  fill  up. 

G.  The  Baltic— The  North  Sea— The  Straits  of  Dover— The 
English  Channel— The  Bay  of  Biscay. 

The  Baltic,  like  the  Black  Sea,  is  of  little  depth. 
We  shall  see  by-and-by  that  its  bed  is  the  seat  of 
very  remarkable  phenomena.     Its  northern  part  is 


38  THE  BOTTOM  OF  THE  SEA. 

slowly  but  steadily  rising,  insomucli  that  the  Gulf 
of  Bothnia  diminishes  in  extent  and  depth  at  a 
certain  constant  rate.  At  the  same  time,  the  southern 
part  of  this  ocean-bed  is  sinking,  and  the  sea  is 
gradually  taking  possession  of  the  lower  plains  of 
Mecklenburg  and  Pomerania. 

The  Skager  Kack  leads  from  the  Baltic  into  the 
North  Sea,  which  is  likewise  of  slight  depth.  Ex- 
cepting a  long  narrow  trough  which  follows  the 
direction  of  the  coast  of  Norway,  the  bed  of  the 
North  Sea  may  be  described  as  an  undulating  plain, 
never  more  than  600  feet  deep.  Some  of  the  greater' 
banks  almost  reach  the  level  of  the  waters ;  others 
are  not  more  than  a  hundred  feet  beneath  the  surface. 
In  this  sea  various  kinds  of  fish  are  abundantly 
nourished  by  marine  worms ;  numerous  sites  covered 
with  algSB  provide  them  with  an  agreeable  retreat ; 
and  the  water,  constantly  beaten  by  the  winds,  is 
plenteously  supplied  with  air  for  the  respiration  of 
its  innumerable  hosts. 

The  shores  of  the  British  Isles  are  very  abrupt,  but 
the  sea  is  of  no  great  depth  until  we  pass  beyond  the 
west  of  Ireland  and  the  Hebrides.  At  the  distance 
of  about  twenty  leagues  from  Valencia  we  find  a 
depth  of  600  feet,  which  increases  westward,  until 
we  arrive  at  the  Telegraphic  Plateau  already  do- 
scribed. 


THE  ENGLISH  CHANNEL. 


39 


The  whole  extent  of  France  and  the  English 
Channel,  of  the  British  Isles  and  the  North  Sea,  forms 
one  great  plateau,  which  is  terminated  on  the  west  and 
on  tlie  north  by  a  steep  declivity.  The  following  sec- 
tion (fig.  11)  will  give  an  idea  of  what  we  mean.  The 
straight   horizontal  line  represents  the  level  of  the 


Fig.  1 1 . — Profile  of  the  Ocean  Floor  from  the  southernmost  point  of  Xorwjiy, 
via  the  St  i-aits  of  Dover,  to  the  10th  degree  of  west  longitude  and  tlie  47ih 
dfgree  of  north  latitude. 

sea.  The  irregular  line  beneath  it  represents  the 
bottom  of  the  sea,  which  resembles  a  vast  plateau  or 
block  of  table-land.  Near  the  coast  of  Norway  we 
find  the  deep  trough,  or  ravine,  already  mentioned. 
To  the  left,  the  soil  slopes  oif  very  gradually  (inter- 
rupted by  a  ridge,  or  bank,  about  the  middle  of  the 
Straits  of  Dover)  ;  but  it  deepens  considerably  in  the 
Channel,  and  then  suddenly  sinks  away,  and  presents 


40  THE  BOTTOM  OF  THE  SEA. 

a  declivity  which  may  be  compared  to  a  rampnit 
a  la  Vauban.  We  may  remark  here  that,  contrary 
to  the  general  opinion,  the  aspect  of  the  coast  olten 
suggests  a  false  idea  of  the  sea- bottom.  When  a 
precipitous  mountain  descends  sheer  into  the  water, 
we  are  apt  to  fancy  the  sea  must  be  very  deep  at 
that  spot ;  whereas,  if  we  try  the  plummet,  it  will 
most  likely  be  found  shallow.  Here,  again,  a  sand- 
bank suggests  a  low  flat  shore  beyond  it,  devoid  of 


ri 

C 

i 

-t> 

.jj 

-u 

,  , 

%. 

■*3 

*3 

->J  -t» 

-w  3^ 

■V 

V 

4-9 

m 

J 

^ 

^i 

o 

O 

c2 
o 

o 

"3 

o 

(M 

CO  o 

CO  (M 

lO 

o 

lO 

CO 

00 

lO 

CO  OS 

(N  .-. 

<M 

CO 

»oo- 

::ilf 

[  T/ie  scale  on  the  left  hand  of  the  diagram  is  in  metres,  hut  the 
depths  are  given  in  equivalents  of  feet.'] 

Fig.  12. — Vertical  Section  oi'  the  Straits  of  Dover. 

rocks ;  we  sail  on  and  drop  the  lead,  but  cannot  touch 
bottom.  Many  examples  of  these  deceptive  appear- 
ances must  have  struck  the  reader  during  our  rapid 
survey  of  the  ocean-floor. 

Notwithstanding  its  steep  shores  the  English 
Channel  is  of  slight  depth.  Notwithstanding  the 
cliffs  which  confront  each  other  on  the  opposite 
coasts  of  England  and  France,  there  is  so  little 
water  in  the  Straits  of  Dover,  that  if  the  level  of 


THE  ENGLISH  CHANNEL.  41 

the  sea  were  reduced  by  sixty  yards  the  two  coun- 
tries would  be  united  by  a  natural  causeway;  nay, 
if  the  water  were  only  drawn  off  to  the  extent  of 
eight  yards  in  depth,  an  island  would  be  left  in  the 
middle  of  the  narrow  passage.  Unhappily  for  the 
enemies  of  England,  the  contrary  of  this  is  more 
likely  to  occur,  as  the  tendency  of  the  soil  in  tliis 
part  of  Europe  is  to  sink,  as  will  be  seen  further  on. 


42  TEE  BOTTOM  OF  THE  SEA. 


THE  WATER  OP  THE  OCEA^. 


1.  Composition  of  Sea- water — Biot's  Apparatus. 

Seas  are  the  products  of  atmospheric  vapou**,  con- 
densed into  fresh-water.  But  the  earth,  with  which 
the  water  came  into  contact,  contains  various  soluble 
matters.  These  were  dissolved  by  the  water,  and 
its  purity  was  irrevocably  lost. 

The  vapour  wliich  is  lifted  from  the  seas  by  the 
action  of  the  atmospheric  currents  may  be  said  to  rise 
in  a  pure  state  ;  in  other  words,  it  is  fresh  water  that 
is  raised.  But,  again,  it  falls  in  the  form  of  rain  or 
snow  upon  the  soil,  over  which  it  passes  slowly  to  its 
destination,  and  thus  becomes  charged  anew  with 
salts  which  it  conveys  into  the  sea.  Every  time 
evaporation  takes  place,  the  vapour  returns  in  the 
form  of  water  laden  with  fresh  matter  from  the  sur- 
face of  the  earth.  This  alternate  migration  of  vapour 
and  water  must  tend  to  augment  continually  the  salt- 
ness  of  the  sea,  and  if  there  were  no  countervailing 
cause,  its  saltness  would  increase  to  the  extreme  point 
of  saturation. 


COMPOSITION^  OF  SEA-WATER. 


43 


The  fact  is,  however,  that  countless  myriads  of  ani- 
mals extract  from  the  waters  of  the  ocean  enough  solid 
matter  to  build  continents  of.  The  foraminiferai,  the 
polypi,  and  the  molluscs  hence  derive  the  calcareous 
coverings  which  form  their  shells  or  skins.  An  esti- 
mate may  be  formed  of  the  stupendous  nature  of  the 
agency  of  these  little  creatures,  by  considering  the 
vast  extent  of  the  beds  of  calcareous  rock  which  form 
part  of  the  earth's  crust,  and  which  are  composed  of 
the  debris  of  creatures  so  small  that  upwards  of  fifty- 
eight  thousand  of  them  have  been  counted  in  a  cubic 
inch  of  chalk.  No  doubt  other  marine  animals  ex- 
tract other  salts  from  the  ocean,  and  we  must  add  to 
their  action  that  of  the  marine  vegetation.  Setting 
tliese  considerations  aside  for  the  present,  the  actual 
composition  of  sea-water  is  found  to  be  as  follows  : — 


Water     .... 

Sea-salt,  or  chloride  of  Bodium 

Chloride  of  magnosiuni     . 

Chloride  of  potassium 

Bromide  of  mugnesia 

Sulphate  of  magnesia 

Sulphate  of  lime 

Carbcmate  of  lime    . 

Residuum,  not  determined,  but  consisting  of 
sulphuretted  hydrogen  gaa,  hydrochlo- 
TtLic  of  anmionia,  &c.  &c.         .         .         . 


9620} 

grains 

27 

1 

5 

4 

0 

4 

0 

1 

1 

•2 

0 

•8 

0 

1 

2-9 


1000-0 


Sea-water,  being  thus   composed,  is  considerabl)' 


44  THE  BOTTOM  OF  THE  SEA. 

heavier  than  fresh-water  of  equal  volume.  Thus,  a 
litre  of  fresh-water  (nearly  If  pint)  weighs  less  than 
a  kilogramme  (exactly  0'''998)  at  the  temperature  of 
68°  Fahrenheit ;  the  same  volume  of  fresh-water  under 
the  same  conditions  would  weigh  1^*027.  But  the 
weight  of  sea-water,  like  its  composition,  is  far  from 
being  constant ;  it  varies  according  to  times  and 
places,  and  even  according  to  the  depth  from  which  it 
is  taken.  Southern  sea-water  is  heavier  than  that  of 
the  northern  hemisphere  in  the  proportion  of  1*0272 
to  1*0262  of  specific  gravity,  owing  to  the  greater 
quantity  of  salt  it  contains.  Off  Cape  Horn  its  specific 
gravity  is  1*028,  the  heaviest  known.  The  upper 
current  of  the  Gulf  Stream  is  lighter  than  the  current 
below,  because  it  is  less  saturated  with  salt ;  but  these 
facts  will  be  further  elucidated  by-and-by. 

As  the  air,  at  whatever  height  we  take  a  sample, 
is  found  to  be  of  the  same  composition,  an  interesting 
question  arises  whether  or  not  the  sea  partakes  of  this 
property  ?  Are  the  gases  which  enter  into  its  com- 
position always  in  the  same  proportions?  These 
questions  are  not  easy  to  solve,  because  the  enor- 
mous pressure  exercised  by  a  column  of  water  many 
thousands  of  yards  in  depth  causes  extraordinary 
difficulties  in  the  construction  of  the  necessary  ap- 
paratus. It  must  be  remembered  that  it  is  essential 
to  obtain  the  water  at  the  required  deptli,  and  brino^ 


8EA-WATER  AT  VABIODS  DEPTUS.  45 

it  to  the  surface  with  all  that  it  contains  in  hermeti- 
cally-sealed vessels.  It  is  not  possible  to  employ 
empty  vessels,  such  as  are  used  for  investigations 
into  the  character  of  the  atmosphere,  contrived  to 
open  at  the  required  depths.  The  water  would 
either  break  the  vessels  or  filter  through  them.  On 
their  approaching  the  surface,  any  gases  that  had 
been  subject  to  the  enormous  powers  of  compression 
of  the  superincumbent  water,  would  dilate  to  an  ex- 
tent which  no  vessel  hermetically  sealed  could  be 
expected  to  resist.  Biot  has,  to  some  extent,  over- 
come these  difficulties  in  the  following  manner. 

He  takes  for  his  vessel  a  hollow  cylinder  of  glass, 
closed  at  one  end  by  a  solid  plate  of  metal,  so  as  to 
resemble  a  pail.  Like  a  pail  also  it  has  a  handle, 
with  a  cord  attached,  by  which  it  is  let  down  into 
the  sea.  This  pail  being  open  to  the  surrounding 
water,  descends  to  any  required  depth  without  injury 
from  the  pressure  of  the  water ;  and  whenever  the 
operator  pleases  he  pulls  a  second  cord,  attached 
to  the  bottom  of  the  pail  by  means  of  an  inverted 
handle,  and  this  causes  the  vessel  to  tip  over.  By 
the  same  cord  he  draws  it  to  the  surface.  It  must 
now  be  observed  that  the  metal  bottom  of  the  pail  is 
double  ;  one  of  its  parts  being  fixed,  the  other  move- 
able like  a  piston,  and  capable  of  descending  in 
the  cylinder  by  its  own  weight  when  the  vessel  is 


1()  THE  BOTTOM  OF  THE  SEA. 

reversed.  In  the  fixed  bottom  there  is  a  small  hole, 
furnished  with  a  valve,  which  opens  from  the  exterior 
to  the  interior,  so  that  the  water  passes  through  and 
fills  the  space  between  the  descending  piston  and  the 
fixed  bottom.  This  being  done,  the  valve  is  closed 
by  the  action  of  a  spring,  and  the  water  contained  in 
the  pail  is  isolated. 

If  this  water  contained  any  quantity  of  compressed 
air,  nothing  would  be  able  to  resist  its  expansive 
power  when  it  was  drawn  to  the  surface,  and  the 
pressure  of  the  exterior  water  ceased  to  act.  It 
would  then  burst  the  apparatus  and  escape.  As  a 
safeguard  against  this  violence,  a  free  issue  is 
prepared,  suflScient  to  serve  for  any  possible  expan- 
sion of  the  air  in  the  w  ater.  In  the  fixed  bottom 
there  is  a  passage  communicating  with  a  bladder, 
which  is  empty  and  folded  up  when  the  apparatus  is 
let  down  into  the  sea,  but  which  receives  whatever 
gas  or  air  the  water  in  the  pail  may  disengage  as  it 
ascends,  and  thus  returns  to  the  surface  more  or  less 
inflated.  The  operator  then  closes  the  stopcocks 
with  which  the  passage  of  communication  between 
the  pail  and  the  bladder  is  fitted ;  and  having  sepa- 
rated the  latter,  he  proceeds  to  measure  and  analyse 
the  air  contained  in  it.  Having  done  this,  he  can 
study  at  his  leisure  the  water  enclosed  in  the  pail, 
and  whatever  matter  it  holds  in  solution. 


SALTNESS  OF  THE  SEA.  47 

2.  Variations  in  the  Saltness  of  Sea-water. 

Water  is  so  much  the  more  heavy  as  it  is  more  salt. 
It  is  not  surprising,  therefore,  that  the  saltness  of  the 
sea  should  increase  with  its  depth.  That  increase  is 
not  indefinite,  because  water  at  a  certain  temperature 
can  only  hold  in  solution  a  given  quantity  of  mineral 
matters. 

We  must  at  once  confess  to  our  ignorance  of  the 
quantity  of  salts  held  in  solution  in  the  profound  depths 
of  the  Ocean.  With  the  apparatus  of  Biot  we  can,  it 
is  true,  obtain  water  from  great  depths.  Still,  it  is 
not  possible  to  operate  at  distances  of  20,000  or 
i^0,000  feet  from  the  surface ;  or,  if  possible,  the 
business  is  at  once  too  costly  and  too  difficult  to  be 
often  attempted. 

Rain  and  evaporation  cause  the  saltness  of  the 
superficial  waters  of  the  sea  to  vary  considerably. 
Evaporation  increases,  rain  diminishes  it.  The 
effects  due  to  these  causes  are,  generally  speaking, 
not  very  apparent ;  but  they  are  very  observable  when 
one  of  them  jiredominates.  If  it  rains  frequently  in 
certain  regions,  the  saltness  of  the  surface  of  the 
sea  is  slight  in  comparison  with  that  of  places  where 
the  clearness  of  the  atmosphere  favours  evaporation. 
It  is  less  at  the  equator  than  near  the  tropics.  It  is 
greatest  at  the  21fc;t  parallel  of  north  latitude,  and 


48  TEE  BOTTOM  OF  THE  SEA. 

the  16th  of  south  latitude,  in  the  Atlantic  Ocean. 
Above  these  latitudes  the  saltness  diminishes  con- 
tinually to  the  polar  regions. 

On  the  other  hand,  we  must  not  forget  that  there 
exists  near  the  equator  a  zone  (the  Equatorial  Calm 
Belt),  where  the  precipitation  of  the  vapour  of  water, 
in  the  form  of  rain,  is  almost  incessant.  To  the 
north  and  south  the  trade-winds  sweep  the  surface 
of  the  sea,  and  the  atmosphere  is  clear,  or  only- 
shadowed  by  clouds  floating  towards  the  region  of 
rains.  We  also  find,  on  approaching  the  poles,  two 
zones  of  variable  winds,  where  frequent  tempests 
disturb  the  air,  and  cause  abundant  condensations. 
The  relation  of  evaporation  and  rain  to  the  saltness 
of  the  sea  is  thus  made  evident. 

In  the  polar  regions  the  saltness  of  the  sea  is  mo- 
dified by  another  cause  not  less  active  than  the 
above — namely,  the  melting  of  the  ice,  accumulated 
like  two  vast  cowls  over  the  extremities  of  the  earth. 
Every  year,  during  the  summer  of  each  hemisphere, 
torrents  of  fresh-w^ater  are  poured  out  towards  the 
temperate  regions.  These  torrents  gradually  mingle 
with  the  salt-water  of  the  ocean,  upon  which  they 
first  flow  along  as  a  river  on  its  bed ;  and  as  a  con- 
sequence of  this,  and  the  other  active  causes  to  which 
we  have  alluded,  the  saltness  of  the  sea  grows  less  at 
the  surface  in  proportion  as  we  approach  the  poles. 


EVAPORATION  OF  THE  SEA.  49 

The  water  which  the  ocean  loses  by  evaporation 
is  returned  to  it  in  full  measure  by  rains  and  rivers. 
It  is  not  so,  however,  in  the  case  of  certain  interior 
seas,  completely  isolated  from  the  ocean,  or  only 
communicating  with  it  by  means  of  a  narrow  channel. 
The  winds  which  blow  upon  such  a  sea  may  be  de- 
spoiled of  their  humidity  by  their  passage  across 
great  continents,  and  the  rivers  themselves  may  not 
bring  a  sufficient  tribute  to  supply  the  loss  caused 
by  a  powerful  evaporation ;  or  it  may  happen  that  the 
quantity  of  water  returned  by  rains  and  rivers  is 
exactly  equal  to  that  which  is  lost  by  evaporation ; 
or,  finally,  the  supply  may  exceed  the  loss.  In 
either  case,  the  result,  as  regards  the  saltness  of  the 
sea,  is  obvious.  In  the  first  case  its  water  will  be 
Salter  than  that  of  the  ocean;  in  the  second,  it  will 
be  about  the  same  ;  in  the  third,  less. 

If  the  interior  sea  communicates  with  the  ocean, 
there  will  generally  be  a  current  in  tlie  channel 
which  unites  them.  This  current  will  float  ships 
into  the  interior  sea  if  that  sea  loses  more  water 
than  it  receives;  but  it  \\ill  bear  them  towards  the 
ocean  if  it  receives  more  water  than  it  loses.  The 
Mediterranean  and  the  Red  Sea  both  receive  the 
waters  of  the  ocean.  The  Black  Sea  and  the  Baltic 
are,  so  to  speak,  too  rich ;  they  contribute  tlieir 
excess  of  water  to  the  neighbouring  seas. 


50  THE  BOTTOM  OF  THE  SEA. 

When  the  interior  sea  is  the  bottom  of  a  bo,sin 
without  issue,  either  the  supply  of  watoi  by  means 
of  rains  and  rivers  must  equal  in  volume  that  which 
is  lost  by  evaporation,  or  the  sea  must  gradually  dry 
up.  Tiie  Caspian  and  the  Dead  Seas  are  both  examples 
in  point.  The  first  is  surrounded  by  calt  steppes, 
where  it  is  easy  to  discover  traces  of  the  lecent  exist- 
ence of  the  waters.  Its  level  is  above  100  feet  below 
that  of  the  Black  Sea,  and  it  is  constantly  decreasing 
in  extent,  and  is  very  salt.  The  Dead  Sea  is  at  pre- 
sent about  1400  feet  below  the  level  of  the  Bed  Sea ; 
yet  travellers  have  recognised  between  the  two  seas 
the  dried-up  bed  of  a  river,  which,  through  causes  not 
yet  ascertained,  has  ceased  to  unite  them.  Since  that 
epoch,  the  Dead  Sea  has  not  received  sufficient  water 
from  the  Jordan  to  supply  the  loss  ocasioned  by  eva- 
poration ;  its  level  has  consequently  sunk  and  its  salt- 
ness  has  proportionately  increased,  until  an  equilibrium 
has  been  established  between  the  supply  and  loss. 

There  are  many  salt  lakes,  both  in  the  Old  World 
and  the  New,  which  owe  their  saltness  entirely  to  tlie 
rivers  which  flow  into  them.  The  delivery  of  water  is 
increased,  and  the  lakes  overflow ;  it  is  diminished,  the 
lake  retires,  and  its  saltness  increases.  When  the 
supply  of  water  is  quite  insufficient  to  compensate  for 
evaporation,  the  lake  dries  up,  and  in  its  place  is 
seen  a  valley  covered  wdth  a  bed  of  salt. 


MATERIALS  WASHED  IN  BY  EI  VERS.  51 

The  composition  ol  sea-water  varies  most  in  the 
neighbourhood  of  the  coasts.  It  is  only  at  a  con- 
siderable distance  from  its  embouchure  that  the 
water  of  a  river  mixes  with  that  of  the  ocean,  and 
the  one  is  often  distinguished  from  the  other  by  a 
well-defined  line.  This  phenomenon  is  most  striking 
at  the  embouchure  of  the  Mississippi.  Tlie  "  Father 
of  Waters  "  rolls  into  the  sea  laden  with  yellow  mud, 
which  forms  a  shifting  promontory  in  the  midst  of 
the  dark  waters  of  the  Mexican  Gulf. 

*'  Suddenly,"  says  a  recent  traveller,*  "  it  seemed 
to  me  that  the  colour  of  the  water  had  changed : 
the  deep  blue  had  become  yellow,  and  the  distinc- 
tion between  them  was  marked  by  a  line  as  straight 
as  if  drawn  with  a  cord,  extending  from  east  to 
west.  Northward,  a  darkish  coast-line,  half  con- 
cealed by  mist,  indicated  the  direction  of  the  land : 
we  were  floating  on  the  waters  of  the  Mississippi. 
Soon  the  speed  of  the  ship  was  slackened,  she  was 
scarcely  able  to  make  way ;  all  at  once  she  stopped, 
her  keel  was  fast  in  the  murl." 

Another  cause  sometimes  tends  to  diminish  the 
saltness  of  the  superficial  waters  near  the  coasts. 
Eain  which  falls  upon  the  steep  or  sloping  shores 
at  once  finds  its  way  into  the  sea.  In  this  case  the 
waves   and   currents  combine   to  mingle  the  fresh 

*  M.  Elisee  Rechia  :  Fragment  d'un  Voyage  h  In  NouveUe-Orlcuna 


52  THE  BOTTOM  01   TUE  SEA. 

and   the   salt   water    together,  and   the   accidental 
anomaly  is  soon  lost  to  observation. 

Fresh-water  is  contributed  even  by  the  bottom  of 
the  sea  itself.  It  is  true  the  phenomenon  of  sub- 
marine springs  is  of  rare  occurreoce,  yet  some  re- 
markable instances  are  known,  and  many  others 
may  have  escaped  notice.  In  some  places,  generally 
near  tlie  shore,  the  sea  may  be  seen  to  bubble,  and 
yet  no  gas  is  disengaged.  The  movement  is  occa- 
sionally so  pronounced  that  the  surface  of  the  sea 
swells  as  with  a  wave ;  and  if,  in  such  a  case,  we  test 
the  water,  it  will  be  found  to  be  less  salt  than  usual. 
If  the  sample  be  taken  from  near  the  bottom,  it  will 
prove  to  be  nearly  fresh ;  indeed,  if  the  source  be 
abundant,  it  will  be  found  to  be  quite  fresh.  The 
effect  of  these  springs,  however,  is  not  traceable  to 
any  considerable  distance,  and  as  they  are  always 
near  the  shore,  we  can  only  regard  them,  in  con- 
nection with  our  subject,  as  objects  of  curiosity. 


3.  Variations  observed  in  the  Gases  contained  in  Sea-water. 

Sea-water  not  only  contains  salts,  but  gases.  Air 
penetrates  into  the  sea,  as  water  penetrates  into  the 
atmosphere,  in  the  state  of  vapour.  Thus  a  kind  of 
exchange  or  reciprocity  of  action  is  established,  and  in 
both  cases  a  sort  of  refinement  or  purification  is  effected 


GAiiES  liV  THE  SEA.  53 

Water  converted  into  vapour  is  disburdened  of  its 
salts ;  air  contained  in  water  becomes  richer  in 
oxygen.  This  gas  plays  a  most  important  part  in 
oceanic  phenomena.  Without  it  no  living  thing  could 
exist  in  the  sea.  Except  for  it,  even  those  beautiful 
algae,  whose  long  and  brilliantly-coloured  ribbons  are 
floated  in  undulating  curves  by  the  marine  currents, 
would  no  longer  charm  the  eye.  The  whole  race 
of  polypi  would  cease  to  construct  their  stony  habi- 
tations, which  are  so  much  admired  by  the  lovers  of 
nature. 

The  deeper  we  penetrate  into  the  ocean  the  more 
abundant  are  the  gases.  The  increase  of  carbonic 
acid  gas  with  the  increasing  depth  is  especially  re- 
markable ;  and  hence  the  gaseous  mixture  found  in 
the  deeper  parts  of  the  sea  is  less  suitable  for  re- 
spiration than  that  which  is  nearer  the  surface.  It 
is  further  to  be  observed  that  the  renewal  of  gases 
in  deep  water  is  effected  with  much  less  facility ; 
and  this  may  be  regarded  as  one  of  the  causes 
which  tend  to  prevent  the  existence  of  organised 
beings  at  a  great  depth.  As  aerial  plants  and 
animals  are  confined  to  the  lower  strata  of  the 
atmosphere,  so  marine  plants  and  animals  are  con- 
demned to  remain  near  the  surface  of  the  waters,  com- 
paratively speaking.  Thus,  the  living  beings  which 
flourish  on  our  globe  are  confined  to  a  very  limited 


64  THE  BOTTOM  OF  THE  SEA. 

Stratum  of  air  and  water,  and  they  reach  their  maxi- 
mum development  where  the  two  atmospheres  meet* 
When  a  volcanic  eruption  takes  place  in  the  sea, 
the  composition  of  the  gases  contained  in  the 
water  is  necessarily  changed  in  the  neighbourhood 
of  the  volcano  by  the  subterranean  emanations. 
Some  seas,  like  the  Caspian,  are  literally  poisoned 
by  volcanic  products,  and  this  to  such  a  degree  that 
it  is  hardly  possible  to  live  near  them.  A  bird  can- 
not hover  above  their  waters  without  the  risk  of 
perishing  from  their  deadly  influence.!  In  the  great 
oceans  the  gases  produced  by  volcanic  eruptions  are 
reduced  to  insignificant  proportions  by  the  action  of 
the  marine  currents. 

*  Notwithstanding  the  general  truth  there  is  in  this  statement, 
organised  creatures  have  recently  been  discovered  in  much  greater 
depths  than  had  been  anticipated. — Tr. 

t  This  was  for  a  long  time  the  popular  notion  concerning  the 
Dead  Sea.  The  fact  is  now  known  to  be  otherwise.  Mr.  Tristram, 
in  that  chapter  of  his  interesting  journal  where  he  describes  "  the 
Dead  Sea  shore,"  mentions  having  seen  a  fine  brown-necked  raven, 
which  flew  quite  across  the  lake,  and  a  kingfisher  actually  sitting  on 
a  dead  bough  in  the  water.  Many  gulls  were  also  fishing  in  their 
customary  manner;  small  flocks  of  pocliard  ducks  skimmed  the 
surface,  and  close  along  the  shore  were  duidins,  redshanks,  and 
wagtails,  and  one  specimen  of  the  desert  wheatcar.  At  tiie  same 
time,  lie  says,  "  it  is  quite  certain  that  no  form  of  either  vertebrate  or 
molluscous  life  can  exist  for  more  than  a  very  short  time  in  the  sea 
itself,  and  that  all  that  enter  it  arc  almost  immediately  poisoned  aiid 
salted  down." — Tr. 


ANIMAL  DEBRIS  IN  THE  HEA.  55 

4.  Solid  Bodies  in  the  Sea — Phosphorescence. 

The  sea  holds  in  suspension  a  great  variety  of 
solid  matters.  In  the  first  rank  are  fish,  which 
float  in  the  liquid  element  as  birds  in  the  air, 
whilst  the  other  living  creatures  of  the  ocean  are 
under  the  necessity  of  finding  a  point  of  support  on 
the  submarine  soil.  The  number  of  creatures  float- 
ing in  the  water  is  enormous.  Many  species  of 
them  congregate  in  shoals,  which  have  sometimes 
been  known  to  cover  hundreds  of  square  leagues  of 
surface,  and  extend  several  hundreds  of  feet  in 
thickness  or  depth.  It  is  not,  however,  to  the 
natural  history  of  animals  that  our  attention  is  now 
Ciilled.  Our  subject  is  the  sea-bottom,  and  it  is  only 
80  far  as  any  creature  lives  on  the  submarine  soil,  or 
leaves  its  spoils  there,  that  we  owe  it  any  special 
regard.  One  passing  observation  may  be  made.  It 
seems  certain  that  such  immense  shoals  of  living 
beings  must  vitiate  the  aqueous  atmosphere  in  which 
they  float,  just  as  any  other  similar  congregation  of 
men  or  animals  would  affect  the  surface  of  the  earth 
and  the  air  they  breathe.  Their  debris  must  un- 
doubtedly be  reckoned  among  the  agents  by  which 
the  basin  of  the  sea  is  more  or  less  modified. 

The  spawn  of  fish  existing  in  such  numbers  forms 
enormous  banks,  and    it  is  to  this  cause  that  the 


56  THE  BOTTOM  OF  THE  SEA. 

phosphorescence  of  the  sea  is  sometimes  due.  M. 
de  Tessan  has  observed  a  phenomenon  of  this  kind 
at  Simon's  Town,  Cape  of  Good  Hope  : — 

"  On  the  10th  of  April,  in  the  evening,  the  sea, 
in  the  roadstead  of  Simon's  Town,  presented  an  ex- 
traordinary phosphorescence  of  the  most  vivid 
character.  At  whatever  points  the  phosphorescence 
was  greatest,  the  water  was  coloured  on  the  surface 
as  red  as  blood,  and  it  contained  such  an  immense 
quantity  of  little  globules  that  it  had  the  consistency 
of  a  syrup.  A  bucket  of  water  taken  up  at  one  of  these 
points,  and  filtered  through  a  piece  of  linen,  left  on 
the  filter  a  mass  of  globules  greater  in  volume  than 
the  water  that  had  passed  through :  in  other  words, 
the  globules  constituted  more  than  half  of  the  whole 
quantity  of  sea-water  taken  up  in  the  bucket. 
Viewed  through  a  magnifying-glass,  these  globules 
presented  the  appearance  of  little  transparent  and 
inflated  bladders,  having  on  their  surface  a  black 
point,  surrounded  with  equally  black  radiating  striae. 
They  had  a  very  perceptible  odour  of  the  sea,  and 
most  probably  they  were  the  spawn  of  fish.  Thus 
isolated  from  the  water,  they  were  highly  phos- 
phorescent; the  least  agitation,  the  least  contact 
made  them  throw  out  a  vivid  greenish  light,  whilst 
the  water  that  had  been  filtered  away  from  them 
had  completely  lost  the  property  of  becoming  phos- 


Fig.  1 3,— rhosphoresceut  Sea  at  Simon's  Town,  Gipeof  Good  Hope. 


FIIOSrnORESCENCE  OF  SPAWX.  69 

phoresceiit  hy  a^^itation.  Pressed  in  the  hand, 
the  mass  of  globules  made  a  sliglit  crackling, 
like  that  of  snow  pressed  between  the  fingers 
After  remaining  about  twelve  hours  in  a  vessel 
it  smelt  like  stinking  fish,  and  was  no  longer 
phosphorescent,  in  which  respect  it  differed  from 
other  organic  matters  which  become  phosphorescent 
when  they  putrefy.  Such  was  the  matter  which, 
as  the  waves  in  which  it  floated  washed  the  shore, 
broke  out  in  vivid  flashes  like  lightning.  This  com- 
parison was  suggested  to  me  by  the  clearness  with 
which  it  lighted  up  the  chamber  that  I  and  my  com- 
panions occupied  in  the  house  of  Mr.  Bull,  though 
it  was  situated  more  than  fifty  yards  distant  from 
the  breakers:  I  even  attempted  to  write  by  the 
light,  but  the  flashes  were  of  too  short  duration. 
The  greatest  part  of  this  matter  was  eventually 
thrown  up  on  the  coast,  where  it  putrefied,  and  spread 
far  and  wide  a  stinking  odour." 

Molluscs,  of  very  small  size,  swimming  in  largo 
numbers  on  the  surface  of  the  sea,  communicate  to 
it  an  artificial  colouring.  This  appearance  might  be 
attributed  to  any  cause  whatsoever — for  example,  to 
mud,  or  any  mineral  matters  held  in  solution.  But, 
independently  of  the  microscope,  which  reveals  the 
structure  of  these  beings,  and  of  the  appearances 
presented  when  the  substance  is  burnt,  and  the  smell 


60  THE  BOTTOM  OF  THE  SEA. 

as  of  burnt  horn  wliich  it  diffuses,  there  is  no 
difficulty  in  determining  the  animal  or  vegetable 
nature  of  such  colouring-matter,  wlien  it  forms 
banks  of  considerable  extent,  far  from  any  coast, 
and  in  deep  sea-bottoms.  The  following  examples, 
from  M.  de  Tessan's  account  of  the  physical  facts 
observed  during  the  voyage  of  the  Venus,  will  give 
an  idea  of  these  phenomena : — 

'^Latitude  21°  50'  N. ;  longitude  19°  48'  W.— We 
had  sounded  a  depth  of  about  1600  feet,  when  it 
was  observed  that  the  colour  of  the  sea  suddenly 
changed.  It  had  become  a  dirty  yellowish-greeu. 
We  took  a  fresh  sounding,  and  marked  more  than 
3000  feet  without  reaching  the  bottom.  The  wate? 
brought  to  the  surface  contained  nothing  remarkable 
but  a  number  of  very  small  transparent  molluscs, 
not  more  than  the  four-hundredth  part  of  an  inch  in 
length,  and  with  yellow  stomachs.  It  was,  perhaps, 
to  the  existence  of  large  numbers  of  these  little 
animals  in  the  deeper  water,  that  the  accidental 
colouring  was  due.  However,  as  the  locality  in 
question  was  only  about  50  leagues  eastward  from 
Cape  Blanco,  on  the  coast  of  Africa,  the  change  might 
be  due  to  a  river  debouching  somewhere  thereabouts. 
The  coloured  band  was  not  above  two  leagues  in 
extent." 

The     Venus     fell    in    with    another    yellowish- 


rUOSVHORESCENOE  OF  A NIHLiLCULJE.  6 1 

coloured  band  m  the  Soutlieru  Atlantic  Ocean. 
Again,  in  the  Pacitic  Ocean,  going  from  Valparaiso 
to  Callao,  the  port  of  Lima,  the  sea  assumed  a  deep 
olive-green  colour,  owing  to  a  thin  mud  or  slime 
which  it  held  in  suspension  : — 

*•  Latitude  13°  50'  S. ;  longitude  76^  51'  W.— During 
the  watch,  we  had  remarked  an  extraordinary  colour 
in  the  water  of  the  sea ;  the  tint  had  changed  to  a 
deep  olive-green.  On  the  22nd  of  May,  the  plum- 
met found  bottom  at  less  than  700  feet,  and  made  us 
aware  of  the  fact  that  the  mud  was  of  the  same 
colour,  but  of  a  clearer  tint.  The  commander,  M. 
Dupetit-Thouars,  by  means  of  dredging,  brought  up 
a  considerable  quantity  of  the  same  mud,  of  which 
some  samples  were  retained.  The  substance  is  al- 
most impalpable,  and  has  no  odour  in  its  natural 
state ;  but  when  calcined,  it  diffuses  a  strong  odour, 
lik,e  that  of  burnt  animal  matter,  and  leaves  a  con- 
siderable quantity  of  a  whitish-grey  ash.  Even  the 
surface-water  contained  this  matter  in  suspension,  for 
the  ship's  hull  at  the  water-mark  was  covered  with 
a  thin  layer  of  it.  It  was  evidently  to  this  matter 
that  the  sea  was  indebted  for  its  deep  olive-green 
colouring,  the  permanence  of  which  in  these  lati- 
tudes, notwithstanding  the  strength  of  the  curyent^ 
which  carries  the  waters  northward,  is  a  curious  fact. 
Aie  we  to  su])pose  that  the  tropical  heat  penetrating 


62  TllE  BOTTOM  OF  THE  SEA. 

the  immense  volume  of  polar  water*  gives  birth  to 
these  microscopic  animalculae  ?" 

In  the  same  latitudes,  with  a  bottom  of  more  than 
5000  feet,  the  sea  presented  the  same  tint,  and 
yielded  the  same  animalculae.  It  would  appear  as  if 
the  great  Peruvian  current,  just  alluded  to,  was 
filled  with  them.  The  same  phenomenon  was  ob- 
served as  the  frigate  approached  New  Zealand, 
where  it  arrived  in  the  month  of  October. 

In  the  polar  regions,  seamen  often  observe  green 
bands  of  considerable  extent,  and  extremely  well 
defined.  They  are  found  to  enclose  myriads  of 
medusae.  These  animals  have  a  yellowish  tint,  which 
combines  with  the  blue  of  the  sea  to  produce  a  green 
colour. 

Enormous  masses  of  microscopic  animals  floating 
on  the  surface  of  the  sea  near  Cape  Palmas,  were 
traversed  by  Tuckey,  whose  ship»«eemed  to  swim  in 
milk.  Other  navigators  have  observed  zones  of  a  red 
colour,  like  carmine,  in  the  Great  Ocean.  The  cause  of 
this  phenomenon  is  analogous  to  those  already  related. 
It  is  owing  to  an  immense  number  of  animalculae,  or 
of  microscopic  algae,  floating  near  the  surface. 

Besides  these  minute  bodies,  sea-water  holds  in 

*  The  great  ocean-current  flowing  from  the  antarctic  pole  towards 
the  equator,  and  known  as  the  whaling-ground  of  the  soutliiru 
Buas. — See  Maury's  9th  Plate.— Tb. 


COLOim  OF  THE  OCEAN.  63 

suspension  many  vegetable  species,  animals  of  various 
strange  forms  and  every  size,  and  a  great  mass  of 
indescribable  debris  Avashed  away  from  the  coasts. 
Too  often  also  the  tnmbled  waters  toss  to  and  fro  the 
broken  remains  of  ships  destroyed  by  the  tempests 
which  in  certain  regions  are  of  frequent  occurrence. 

5.  Colour  of  Sea-water — To  what  extent  influenced  by  matters  held 
in  suspension,  by  the  Bottom  of  the  Sea,  and  by  the  agitation 
of  the  Water. 

What  is  the  colour  of  sea -water?  Captain  Scoresby 
likens  the  general  aspect  of  glacial  seas  to  the  blue 
of  the  deep  ocean.  The  finest  indigo,  or  celestial 
blue,  represents,  according  to  M.  Costoz,  the  colour 
of  the  Mediterranean.  The  Atlantic  has  displayed 
to  the  eyes  of  Captain  Tuckey  a  tint  so  rich,  that  he 
has  tried  to  satisly  his  sense  of  poetical  justice  by 
calling  it  a  living  azure.  Taking  a  hint  from  these 
various  expressions,  we  are  disposed  to  think  the  sea 
has  the  same  colour  as  fresh  water  running  from  a 
bed  of  snow  or  a  glacier.  When  the  quantity  is 
small,  such  water  indeed  appears  to  be  colourless ;  but 
when  a  great  volume  of  it  is  seen,  it  assumes  a 
beautiful  blue  colour. 

The  Ocean  always  presents  this  reflected  blue,  more 
or  less  deep  in  tint — that  is  to  say,  more  or  IcbS 
mingled  with   white   light — if    the   causes  already 


G4  THE  BOTTOM  OF  THE  SEA. 

(^numerated  do  not  modify  it  in  various  ways,  and 
if  the  bottom  of  the  sea  itself  does  not  further 
complicate  the  phenomenon  by  superimposing  upon 
the  colour  of  the  water  its  own  reflected  hue. 

If  the  bottom  be  of  a  more  intense  colour  than  the 
sea,  its  reflected  hue  will  not  be  much  affected. 
Thus,  M  hile  a  yellowish  sand  will  change  the  tint  of 
the  blue  water  to  green,  a  very  bright  yellow  will 
make  the  water  itself  appear  of  that  tint,  because  the 
lesser  intensity  of  the  blue  does  not  affect  the  yellow 
sufficiently  to  make  a  green.  Tuckey  observed,  at 
Loaiigo,  that  the  sea  was  of  the  colour  of  blood ; 
the  bottom  was  very  red.  In  other  places,  where 
the  bottom  might  be  of  a  similar  but  less  lively 
colour,  the  sea  would  not  appear  red,  but  orange,  or 
even  yellow. 

The  influence  of  the  bottom  on  the  tint  of  the  sea 
would  appear  to  be  limited  to  those  cases  in  which 
the  depth  is  very  slight.  In  fact,  the  water  of  the 
sea  absorbs  so  rapidly  the  rays  of  light,  that  in  no 
great  degree  of  thickness  it  becomes  opaque.  There 
are,  indeed,  instances  which  seem  to  imply  the  con- 
trary. Among  other  observations,  the  following, 
made  by  M.  de  Tessan  near  Cape  Agulhas,  on  the 
southern  coast  of  Africa,  seems  to  show,  that  even  in 
the  case  of  great  depths  the  bottom  may  have  a 
sensible  influence  on  the  colour  of  the  water  : — **  The 


REFLECTION  FROM  TRE  SEA-BOTTOM.  6f 

sea,"  he  says,  "  has  very  sensibly  cliaiiged  in  colour 
since  our  arrival  upon  the  bank  of  Cape  Agulhas  this 
morning.  As  we  are  sailing  in  the  direction  of 
the  current,  which  bears  us  rapidly  along,  this  varia- 
tion of  tint  cannot  be  ascribed  to  the  colouring  of  the 
water  itself.  We  are  compelled  to  conclude  that  it 
is  the  effect  of  the  colour  of  the  sea-bottom,  the 
yellowish  tint  of  which,  traversing  the  water,  and 
mingling  with  its  normal  blue,  produces  the  greenish 
hue  that  we  have  observed."  As  the  depth  is 
between  600  and  700  feet  at  this  point,  the  solar 
light  reflected  from  the  bottom  ha  1  traversed  about 
1300  feet  of  water  without  being  extinguished  ;  since, 
on  being  reflected  back  to  the  surface,  it  >\as  still  so 
intense  as  to  influence  the  colour  of  the  water. 

The  contradiction  between  this  fact  and  the  theory, 
is  only  in  appearance.  Let  two  surfaces — the  one 
bright,  but  small  in  extent;  the  other  less  bright, 
but  of  much  larger  size — be  viewed  through  an  im- 
perfectly diaphanous  body.  Then  let  them  be  re- 
moved to  a  distance  simultaneously,  and  it  will  be 
found  that  for  a  considerable  time  after  the  small 
bright  surface  has  disappeared,  the  larger  and  duller 
will  be  visible.  It  is  easy  to  perceive  that  the 
colouring  of  the  sea,  as  witnessed  at  Cape  Agulhas, 
is  a  phenomenon  of  the  same  kind.  The  bank  is  a 
surface  of  very  considerable  extent,  feebly  illuminated, 


66 


THE  BOTTOM  OF  THE  SEA. 


and  is  seen  from  a  great  distance,  by  its  reflected  light, 
through  an  imperfectly  diaphanous  medium. 

To  appreciate  correctly  the  colour  of  the  sea-bottom, 
we  must  be  on  our  guard  against  a  very  common  illu- 
sion. Why  should  a  white  sand  change  the  colour  of 
the  watei-,  or  affect  it  otherwise  than  with  a  slight 
tint  of  white  ?     To  answer  this  question,  we  must  re- 


Fig.  14. — Incidence  of  the  Rays  of  Light  on  a  Culm  Sea. 

member  that  sand  is  white  when  it  is  taken  out  of  the 
water  and  dried.  If  we  throw  upon  it  rays  of  red,  or 
green,  or  any  other  coloured  light,  the  sand  will  appear 
of  that  colour.  Water  seen  by  reflection  appears 
blue ;  seen  by  transparency,  it  appears  green.  As 
the  sand  at  the  bottom  of  the  sea  receives  a  green 


COLOUR  OF  THE  WAVES.  C7 

light,  it  cannot  appear  white,  and  the  greonisli  tint 
which  it  presents  ra ingles  with  that  of  the  water. 
In  a  word,  it  is  necessary  in  all  cases  to  remember 
that  the  bottom  of  the  sea  receives  a  green  light,  and 
not  the  white  light  which  falls  upon  the  surface. 

When  the  surface  of  the  sea  loses  its  uniformity 
the  foregoing  remarks  cease  to  be  applicable.     Un- 


M^-  — 


Kig.  15. — Incidence  of  tlie  Unja  of  Light  on  the  Waves  of  the  Sea. 

dnlations  or  waves  cause  light  wliich  has  traversed 
the  water  to  reach  the  eye  of  the  observer  at  the  same 
time  as  the  light  reflected  from  it.  The  former  is 
that  which  falls  on  the  anterior  part  of  a  wave,  and, 
being  reflected,  traverses  the  superior  part  of  the  wave 
following  before  reaching  the  eye.  This  transmitted 
light  is  green.     If  it  dominates  tlie  reflected  light, 


08  TUE  BOTTOM  OF  THE  SEA. 

which  is  blue,  the  wave  will  appear  greeuish-yellow. 
Further,  it  is  obvious  that  the  difterent  orientations 
of  the  wave  relative  to  the  position  of  the  sun  must 
contribute,  as  much  as  its  changes  of  form,  to  vary 
the  play  of  light.  This  optic  property  of  the  waves 
enables  us  to  recognise  afar  off  a  change  in  the  win'1, 
as  it  produces  a  different  tint  in  the  changing  surface 
of  the  sea. 


6.  Measure  of  Temperature  at  the  Bottom  of  the  Sea. 

The  attempt  to  ascertain  the  temperature  at  the 
bottom  of  the  sea  at  any  given  time  is  surrounded 
with  as  many  difficulties  as  the  procuring  of  water 
from  certain  depths.  The  thermometer  is  subjected 
not  merely  to  the  influence  of  temperature,  but  to  the 
pressure  of  the  water  by  Avhich  it  is  environed.  Of 
slight  importance  when  the  depth  is  inconsiderable, 
this  pressure  becomes  enormous  when  the  descent  is 
measured  by  thousands  of  yards. 

M.  Despretz  has  proposed  to  leave  the  thermo- 
meter open,  in  such  a  manner  that  the  pressure  would 
be  sustained  both  by  the  interior  and  the  exterior  ol 
the  tube.  It  is  generally  preferred  to  enclose  the  in- 
stiument  in  some  very  solid  envelope,  and  close  it 
hermetically.  This  envelope,  formed  of  iron  or  cop- 
per, is  a  good  conductor  of  heat.     The  thermometer 


TEMPERATURE  OF  THE  i^EA  (JU 

whicli  it  protects  will,  therefore,  soon  indicate  an 
equilibrium  of  temperatui'e  between  itself  and  the 
surrounding  water. 

The  temperature  of  the  deeper  waters  is  not  the 
same  as  that  of  the  superficial  mass.  It  is  therefore 
necessary  to  employ  instruments,  so  constructed  as  to 
keep  a  record  of  the  extreme  temperatures  through 
which  they  are  passed.  To  effect  this,  P^ron  en- 
closed the  instrument  in  a  tube  made  of  a  substance 
that  was  a  bad  conductor  of  heat.  This  apparatus, 
being  immersed  for  a  sufficiently  long  time,  at  lengtli 
acquired  the  temperature  of  the  w^ater  that  surrounde  I 
it,  and  being  quickly  withdrawn,  there  was  no  time 
for  the  heat  to  escape  before  the  indication  was  read  off". 

Bunten  has  attained  the  same  end,  by  inventing  what 
he  calls  the  "  Thermometer  Plunger."  The  instru- 
ment is  put  into  a  tube  closed  by  a  valve,  which  opens 
from  the  exterior  to  the  interior ;  thus  allowing  the 
water  of  the  sea  to  enter,  but  preventing  it  from  re- 
turning when  tlie  apparatus  is  withdrawn.  The  ther- 
mometer, therefore,  is  brought  to  the  surface  sur- 
rounded with  sea- water;  but  it  is  easy  to  see  that  we 
cannot  be  sure  of  the  depth  from  which  the  water  is 
tiiken,  as  in  the  case  of  Peron's  instrument.  Finally, 
the  thermometer  is  not  protected  from  the  pressure 
of  the  water.  Bunten's  Plunger,  therefore,  is  not 
available  for  deep  thermometric  soundings. 


70  THE  BOTTOM  OF  THE  SEA. 

Perhaps  the  best  methoJ  discovered  up  to  the  pn^- 
sent  time  consists  in  enclosing  one  of  Walferdin's 
metastatic  thermometers  in  a  strong  box  of  wrought- 
iron  or  copper,  noting  on  the  return  of  the  instrument 
the  lowest  temperature  that  it  has  marked.  Some- 
times, however,  the  box  will  be  found  crushed. 


7.  Diminished  Temperature  of  the  Sea  in  proportion  to  the  Dtpth 
— Irregularities  introduced  in  this  law  by  tlie  iaflucncij  of  Sub- 
marine Currents — Temperature  at  the  Bottom  of  the  Oeeaa 
constant  and  uniform— Principal  causes  of  Submarine  Currents. 

The  temperature  of  the  atmosphere  diminishes  in 
the  degree  that  we  ascend  above  the  level  of  the  sea  ; 
that  of  the  sea  generally  diminishes  in  the  degree 
that  we  descend  below  its  surface.  It  varies  but  little 
from  day  to  night,  and  even  from  season  to  season. 
At  no  great  depth  it  ceases  to  vary  at  all. 

The  surface  is  hottest  at  the  equator;  it  is  frozen 
at  the  poles.  Between  these  extreme  latitudes  there 
is  a  succession  of  diminishing  temperatures,  but  they 
are  far  from  decreasing  in  regular  gradation  from  the 
equator  to  the  poles.  The  water  is  influenced  by 
marine  currents,  which  have  the  effect  of  masking  the 
otherwise  regular  law  of  decrease. 

The  law  which  varies  the  temperature  according  to 
the  depth  is  also  complicated  by  accidental  causes. 
Often  marine  currents  flow  one  above  another — the 


TEMPERATUUE  OF  THE  SEA.  71 

one  being  cold,  the  other  hot ;  their  directions  also 
cross  each  other  in  a  thousand  ways.  There  may  thus 
be  many  successive  beds  or  strata  of  currents,  their 
density  in  each  case  being  the  greater  in  proportion 
to  the  depth  from  the  surface  at  which  they  are  situ- 
ated. As  a  proof  that  such  different  currents  really 
exist,  it  may  suffice  to  mention  the  suddenness  with 
which  the  thermometer  varies  after  passing  through 
a  certain  depth  of  water,  and  then  continues  constant 
while  the  plummet  descends  through  a  lower  bed. 

Thermometric  soundings  have  marked  a  tempera- 
ture of  41''  Fahr.  in  the  latitude  of  43°  and  37°  under 
the  equator,  at  the  same  depth,  of  somewhat  less  than 
6,000  feet.  This  agrees  with  the  direction  of  the  sub- 
marine currents,  coming  respectively  from  the  poles 
and  from  the  equator.  In  the  torrid  zone  between 
33°  and  34°  Fahr.  have  been  indicated  at  a  depth  of 
12,000  feet,  whilst  the  temperature  at  the  surface  was 
about  80°  Fahr.  This  result  will  be  thought  less  sur- 
prising if  we  bear  in  mind  that  while  fresh-water 
attains  its  maximum  density  at  39°  5'  FaLi.,  average 
sea-water  does  not  arrive  at  its  degree  of  maximum 
density  until  it  passes  its  freezing-point  (27°  2')  and 
reaches  the  temperature  of  25°  6'. 

As  sea-water  is  not  easily  penetrated  by  the  rays 
of  the  sun,  it  keeps  pretty  nearly  at  the  temperature 
of  the  locality  where  it  has  been  detained  for  any 


72  THE  BOTTOM  OF  THE  SEA. 

length  of  time.  Thus  the  play  of  the  polar  waters 
makes  itself  known  to  the  mariner  by  a  fall  in  the 
temperature  of  the  sea,  and  the  equatorial  currents 
carry  with  them  into  the  arctic  zones  a  warm  and 
grateful  reminiscence  of  the  sunny  climes  from  which 
they  have  descended. 

In  general,  the  density  of  a  current  is  in  inverse 
proportion  to  its  degree  of  heat,  and  accordingly, 
overlying  currents  show  a  decreasing  temperature 
according  to  their  depth.  But  in  the  polar  seas  this 
is  not  so.  The  temperature  there  increases  with  the 
depth,  within  certain  limits,  and  thus  assists  in  fusing 
the  lower  part  of  the  ice.  To  account  for  this 
anomaly,  snow  and  ice  are  bad  conductors  of  heat. 
Farmers  and  gardeners  are  well  acquainted  with  the 
fact  that  a  covering  of  snow  keeps  the  earth  warm  in 
winter.  The  effect  of  ice  in  the  arctic  regions  is  similar. 
It  has  been  proved  by  thermometric  observations  that, 
at  a  surface  temperature  of  52°  below  zero  (Fahr.), 
the  water  under  a  bed  of  ice  thiity-two  feet  thick  re- 
mained relatively  hot,  its  temperature  not  liaving 
descended  below  28°  4'  Fahr. 

Thus  sea-water  is  hottest  near  the  surface  in  the 
neighbourhood  of  the  equator,  while  in  the  arctic 
regions  it  is  hottest  at  a  certain  depth,  and  coldest  in 
its  upper  stratum.  The  temperature  of  the  sea-bottom 
is,  however,  uniform  over  all  the  world,  and  differs 


TEMPERATURE  OF  THE  MEDITERRANEAN.        73 

little  from  32^  Fahr.,  or  five  degrees  above  its  freezing- 
point. 

In  the  case  of  landlocked  seas  there  is  not  this  great 
difference  between  the  temperature  of  the  surface  and 
of  the  lower  strata.  The  lAlediterranean,  for  example, 
receives  the  surface-waters  of  the  ocean  through  the 
Straits  of  Gibraltar,  whilst  its  deeper  waters  flow  out- 
wards.* Consequently,  it  is  the  heated  water  of  the 
ocean  which  penetrates  into  this  interior  §ea;  and  the 
action  of  the  sun  being  upon  a  closed  basin,  so  to 
speak,  and  by  far  more  constant  than  upon  the  ocean, 
which  is  traversed  by  the  polar  waters  rushing  in  a 
mighty  torrent  to  sun  themselves  in  the  torrid  zone, 
the  bottom  of  the  Mediterranean  cannot  possibly  be 
so  cold  as  the  bottom  of  the  ocean  itself.  The  Red 
Sea  presents  the  same  phenomena,  in  this  respect,  as 
the  Mediterranean.  The  currents  of  Babelmandeb 
are  analajrous  to  those  of  Gibraltar.  The  Red  Sea  is 
one  of  the  hottest  expanses  of  water  on  the  globe. 
Life  pulsates  in  every  corner  and  recess  of  it,  and 

*  A  very  curious  iucidtnt  first  suggested  the  existence  of  a  sub- 
marine current  in  the  Straits  of  Gibraltar.  A  cortair  brig  sunk  in 
sight  of  Ceuta.  and  disappeared.  At  tliis  point  tlie  current  runs 
very  strong',  and,  of  eourse,  from  ^ve^t  to  east.  What  then  was  tho 
surprise  of  everybody  to  see  the  brig  reappear  some  time  afterwards 
muny  leagues  we>t\vard  of  the  pcjint  where  she  h:id  sunk  !  It  is 
plain  that  the  vessel  must  have  been  drifted  to  that  pi)int  by  a  sub- 
marine current  running  in  the  contrary  direction  to  the  current  od 
ii.csur.'aoo 


74  THE  BOTTOM  OF  THE  SEA. 

there  the  polypi  erect  their  most  gigantic  rampcarts 
of  stone. 

If  we  were  to  sink  a  well  on  the  shore  to  the  depth 
of  12,000  feet,  the  temperature  at  its  bottom  would 
be  about  300°  Fahr.  Yet  we  have  just  seen  that  the 
temperature  at  the  bottom  of  the  sea  is  nearly  con- 
stant at  32°.  This  fact  is  sufficient  to  prove  that  the 
water  of  the  ocean  exercises  an  immense  influence  on 
the  distribution  of  temperature  over  the  surface  of 
the  earth. 

The  Ocean  is  in  turn  affected  by  heat,  even  to  its 
lowest  abysses.  Inequalities  of  temperature  and  of 
saltness  give  birth  to  currents  both  on  its  surface 
and  in  its  depths.  The  former,  however,  are  more 
generally  due  to  the  action  of  the  constant  winds. 
By-and-by  we  shall  have  to  consider  the  action 
exercised  by  cun^ents  upon  their  bed. 


8.  Cause  of  Waves — Their  Height — Thickness  of  the  Mass  of  Water 
in  motion — Ground-swells — '  Raz  de  Mare'y" — Waves  of  Trans- 
lation— Measure  of  a  Wave  of  TransLition,  and  of  its  Speed,  in 
the  Pacific  Ocean — Tides — Ke'sume. 

When  winds  have  not  the  constancy  of  the  Trades, 
they  force  the  surface  of  the  sea  into  heaps,  and 
plough  it  in  furrows  more  or  less  deep :  in  a  word, 
they  cause  waves.  This  movement  of  the  water  does 
not  extend  to  any  considerable  depth. 


HEIGHT  OF  WA  VES.  75 

The  highest  wave  observed  by  M.  de  Tessaii,  during 
the  voyage  of  the  Venus,  measured  about  24  feet 
from  its  crest  to  the  bottom  of  its  cavity.  The  great- 
est height  admitted  by  Humboldt,  and  at  a  distance 
from  any  coast,  is  37  feet.  As  to  the  mass  of  water  set 
in  motion,  observations  were  made  by  M.  Siau,  in  St. 
Paul's  Bay,  Isle  of  Bourbon,  which  seem  to  show  that 
it  does  not  exceed  a  thickness  of  600  feet.  But  the 
height  of  the  wave  is  supposed  to  furnish  a  clue  to  the 
depth  of  the  agitation  it  causes.  Weber  concluded, 
from  his  celebrated  experiments,  that  every  wave 
propagates  its  motion  to  a  depth  of  about  350  times 
its  own  height.  If  so,  a  wave  only  6  feet  in  height 
would  stir  the  North  Sea  to  its  lowest  abysses,  while 
a  wave  30  feet  high  would  make  itself  felt  to  a  depth 
of  10,000  feet.  However  this  may  be,  we  know  that 
the  movement  becomes  very  feeble  even  at  a  slight 
depth,  and  it  must  soon  become  altogether  insensible, 
even  if  it  continues  to  extend  itself,  because  Weber 
himself  has  demonstrated  that  it  decreases  in  geo- 
metrical proportion  according  to  the  depth. 

So  long  as  a  wave  extends  its  motion  downwards 
in  a  deep  place,  it  produces  no  effect  on  the  soil. 
Let  it,  however,  wash  against  a  bank  or  a  shore,  and 
it  begins  to  play  a  part  well  worthy  of  observation. 
Sometimes,  in  combination  with  local  currents,  it 
produces  very  curious    phenomena.     For   example. 


76  TEH  BOTTOM  OF  THE  SEA. 

near  Callao,  the  port  of  Lima,  a  considerable  dike  of 
rolled  stones  parallel  to  the  shore  has  been  thrown  up. 
Its  height  in  some  parts  is  nearly  20  feet.  On  the 
landward  side  it  is  steepest,  and  on  the  other  descends 
towards  the  sea  with  a  gentle  slope;  the  rolled 
stones  of  which  it  is  composed  are  spherical  or  oval 
in  shape.  To  account  for  its  existence,  there  is,  at 
some  distance  off,  between.  Callao  and  Moro-Solar,  a 
cliff,  which  measures  some  140  feet  in  height.  Its 
base  is  incessantly  battered  and  eaten  away  by  the 
waves,  and  the  debris  is  carried  away  northward 
by  the  current.  In  this  remarkable  instance  the 
current  transports  the  materials  of  which  the  dike  is 
constructed,  and  the  waves  build  them  up. 

Where  a  marine  current  passes  over  a  level  bottom 
and  comes  to  a  gentle  slope,  its  speed  is  a  little  ac- 
celerated by  reason  of  the  confinement  of  its  bed ; 
but  this  increased  speed  is  lost  again  when  the  ob- 
stacle has  been  passed.  The  case  is  different  if  the 
bottom  of  the  sea,  instead  of  becoming  gradually 
higher,  rises  abruptly.  A  wave  is  then  produced, 
which  propagates  itself  under  the  water,  and  causes 
what  is  known  as  a  ground-swell.  This  wave  aug- 
ments as  it  approaches  the  shore,  and,  advancing 
rapidly,  breaks  in  a  mass  of  foam  which  escapes  from 
beneath  the  liquid  bulk.  If  the  shore  be  steep,  it  hurls 
itself  against  it,  and  throws  an  immense  head  of  foam 


RACE  OF  THE  TIDE  7? 

to  a  great  height.  There  is  a  rock  in  the  Marianne 
Isles  known  as  '*  Lot's  Wife,"  which  stands  l^>50  feet 
above  its  base,  yet  the  foam  is  thrown  to  its  summit. 

Mr.  Scott  Kussell  has  testified  from  experience, 
that  an  abrupt  rise  in  the  bottom  of  tlie  sea  (under 
the  circumstances  alluded  to  above)  causes  an  elevii- 
tion  of  the  water  over  tliat  particular  spot.  The  rise 
of  the  water  is  as  abrupt  as  that  of  the  sea-bottom, 
and  a  ship  passing  over  it  experiences  a  shock  so 
violent  as  to  induce  the  belief  that  it  has  struck  on 
a  rock.  This  fact  is  familiar  to  observers  accustomed 
to  cross  the  sea,  and  there  can  be  no  mistake  as  to 
the  occasional  violence  of  the  shock,  when  we  recall 
that  a  whaler  was  dismasted  by  this  cause  on  the 
coast  of  Chili,  in  1837. 

Sometimes,  particularly  in  the  neighbourhood  of 
the  Antilles,  a  tumultuous  movement  of  the  sea  is  pro- 
du(;ed  near  the  coast,  whilst  everywhere  else  within 
the  field  of  immediate  observation  there  is  a  perfect 
calm.  This  phenomenon  is  always  connected  either 
with  a  volcanic  eruption,  or  an  earthquake,  or  the  pas- 
sage of  a  cyclone  at  some  distance.  An  experience 
related  by  Dr.  Kooke  as  having  occurred  to  him  at 
the  Sandwich  Islands  is  a  striking  example  of  the 
Raz  de  Maree  (Race  of  the  Tide)  caused  by  an  earth- 
quake and  a  vulcanic  eruption.  His  account  of  the 
phenomenon  is  substantially  as  follows : — 


78  THE  BOTTOM  OF  THE  SEA. 

On  the  7th  of  November,  1837,  during  fine  weather, 
and  in  the  absence  of  any  perceptible  shock  of  earth- 
quake, the  sea  was  all  at  once  moved  in  an  extraor- 
dinary manner.  First,  it  retired  so  great  a  distance 
from  the  shore  as  to  leave  the  reef  which  surrounds 
the  island  (Maui)  dry.  The  inhabitants,  fearing  no 
harm,  collected  on  the  reef  to  gather  up  the  fish 
which  the  sea  had  left  on  retiring,  and  were  memly 
engaged  in  this  occupation  when,  after  some  moments 
of  repose,  the  sea  suddenly  returned  with  extreme 
rapidity,  and,  advancing  like  a  wall,  engulfed  every 
living  being.  The  phenomenon  was  not  everywhere 
accompanied  by  events  so  tragic.  Even  at  Honolulu, 
where  Dr.  Eooke  himself  observed  it,  the  movement 
of  the  sea  was  not  nearly  so  considerable :  neverthe- 
less, all  the  time  that  it  lasted  the  mean  level  of  the 
sea  was  everywhere  about  five  feet  lower  than 
ordinary.  The  conclusion  is  that  the  island  itself 
was  lifted,  bodily,  five  feet  above  the  position  it  habit- 
ually occupied,  and  to  which  it  returned. 

While  the  sea,  and  as  we  suppose  the  land,  were 
thus  strangely  moved,  the  volcano  of  Mauna-Kea,  in 
the  island  of  Maui,  gave  manifest  signs  of  increased 
activity.  At  this  very  time  also  the  inhabitants  of  Aca- 
pulco,  situated  to  the  east  under  the  same  parallel,  were 
kept  in  perpetual  fear  by  undulating  movements  of 
the  earth,  which  came  from  the  direction  of  the  west. 


Fig.  16. — Rising  of  the  Sea  at  .Acapulca 


FAIiTHQVAKE  WAVKS.  81 

Earthquakes  are  always  accompanied,  on  the 
coasts,  by  movements  of  the  sea  more  or  less  con- 
siderable, and  it  is  this  part  of  the  phenomenon  which 
has  caused  the  greatest  disasters.  To  the  movement 
of  the  sea,  again,  is  added  a  temporary  or  permanent 
change  of  its  level. 

During  the  earthquake  of  1820  the  level  of  the 
sea  at  Acapulco  remained  during  two  hours  at  about 
30  feet  below  the  points  of  the  coast  which  corre- 
sponded with  its  ordinary  level.  A  part  of  the  road- 
stead was  left  dry.  After  two  hours  the  sea  returned, 
and  rose  from  four  to  five  yards  above  its  ordinary 
level — that  is  to  say,  from  40  to  45  feet  above  the 
point  to  which  it  had  receded :  it  then  oscillated 
about  its  ordinary  position,  and  finally  resumed  its 
old  relative  level.  There  can  be  no  doubt  that  the 
soil  of  Acapulco  was  itself  raised  during  this  two 
hours  to  the  height  mentioned,  and  afterwards  settled 
down  again  as  described.  The  effect  of  the  raz  de 
marie  was  terrible.  The  sea,  resuming  possession  of 
its  bed,  advanced  upon  the  land  like  a  wall  witli  ex- 
treme rapidity;  and  then,  overleaping  its  ancient 
limits  by  the  impetus  of  its  return,  oveiiluew  what- 
ever opposed  its  progress,  and  destroyed  a  part  of 
the  city. 

Similar  movements  of  the  sea  accompanied  the 
earthquake  which  destroyed  Talcaguana,  on  the  coast 

G 


82  THE  BOTTOM  OF  THE  SEA. 

of  Chili ;  only  in  this  case  the  soil  remained  elevated 
some  five  or  six  feet  above  its  former  position.  After 
the  earthquake  which  destroyed  Old  Callao,  on  the 
contrary,  the  soil  was  found  to  be  permanently 
lowered  some  four  or  five  feet.  The  effect  of  the 
raz  de  marh  was  similar  to  the  preceding. 

It  is  obvious  that  earthquakes  which  extend  under 
the  ocean  must  stir  the  waters  to  their  most  profound 
depths.  They  give  rise  to  a  phenomenon  which  has 
been  named  by  Mr.  Scott  Russell  the  "  Wave  of 
Translation."  He  has  demonstrated  that  the  move- 
ment of  the  water  is  as  great  at  the  bottom  of  the 
sea  as  at  its  surface — a  fact  that  has  been  verified  by 
the  transport  of  objects  that  were  lying  at  the  bot- 
tom. Further,  the  wave  advances  by  forming  a 
swelling  on  the  surface  without  breaking  like  other 
waves,  and  its  speed  of  propagation  is  proportional  to 
the  square  root  of  the  depth.  If  its  course  be  ob- 
structed by  an  abrupt  elevation  of  the  sea-bottom, 
its  effects  will  be  exaggerated  and  complicated  with 
those  of  the  ground-swell.  As  it  reaches  the  shore  it 
produces  the  raz  de  marie. 

Lisbon  was  destroyed  on  the  1st  of  November, 
1755,  by  the  most  violent  and  most  extended  earth- 
quake on  record.  The  shock  was  felt  on  the  same 
day  oveT  the  North  Atlantic  Ocean ;  between  Spain, 
the  Antilles,  and  Newfoundland  ;  in  Canada  •  in  Great 


EARTHQUAKE  WAVES,  8H 

Britain ;  on  the  coasts  of  Sweden  and  the  shores  of 
the  Baltic  ;  in  Germany,  Switzerland,  Italy ;  and  i» 
the  North  of  Africa.  It  was  accompanied  by  a  huge 
wave  of  translation,  that  swept  the  coasts  of  Spain, 
and  attained,  at  Cadiz,  a  height  of  60  feet.  It  inun- 
dated the  ports  of  Madeira.  A  vast  bulk  of  water 
rushed  violently  into  the  marketplace  of  a  city  in 
Ireland  (Kinsale).  The  sea  rose  and  fell  at  Tangier  ; 
and,  though  the  soil  was  not  deranged,  an  extraor- 
dinary movement  was  perceptible  in  England,  both 
in  the  waters  of  the  interior  and  on  the  seacoasts. 

On  the  23rd  of  December,  1854,  at  a  quarter  be- 
fore 10  in  the  morning,  the  Russian  frigate  Diana 
felt  several  shocks  at  the  entrance  of  the  Bay  of 
Simoda,  in  Japan.  At  10  o'clock  a  huge  wave  over- 
whelmed the  city.  A  second  wave  immediately  fol- 
lowed the  first,  and  when  it  retired  every  house  was 
found  to  be  thrown  down.  The  frigate,  after  striking 
several  times,  foundered  on  the  shore.  Some  hours 
later,  at  a  distance  of  nearly  5,000  miles,  waves  of 
an  unusual  height  broke  upon  the  shores  of  Cali- 
fornia. During  the  intermediate  time  the  same 
phenomenon  had  been  observed  in  the  islands  of  the 
Pacific :  thus,  in  a  few  hours,  the  waves  had  traversed 
the  Great  Ocean.  By  comparing  the  various  obser- 
vations, it  was  ascertained  that  the  breadth  of  each 
wave  was  about  250  miles,  and  its  velocity  about  440 


84  THE  BOTTOM  OF  THE  SEA. 

miles  an  hour.  The  mean  depth  of  the  ocean  be- 
tween Japan  and  California  is  from  12,000  to  13,000 
feet. 

Again,  as  the  tides  are  movements  produced  in  the 
great  mass  of  the  waters,  they  are  likely  to  cause 
certain  effects  on  the  bottoms  of  seas  which  it  would 
be  useful  to  ascertain.  But  that  action  takes  place 
near  the  surface,  and  is  difficult  to  distinguish  from 
the  effects  of  the  weaves. 

All  the  causes  of  the  agitation  of  the  sea  are  ex- 
terior to  it.  However  far  their  influence  extends,  we 
may  yet  conceive  that  a  limit  exists  beyond  which  it 
ceases  to  produce  itself.  The  "  waves  of  translation  " 
alone  heave  up  the  ocean  from  its  lowest  depths ; 
but  this  phenomenon  only  takes  place  in  connection 
with  earthquakes,  and  is,  happily,  of  rare  and  but 
momentary  occurrence. 

Marine  currents  extend  to  a  great  depth;  they 
sweep  through  the  ocean  one  above  another,  and  it 
has  been  proved,  by  the  soundings  made  during  the 
last  few  years,  that  their  effects  extend,  we  may  al- 
most say,  to  the  lowest  deeps.  It  has  been  ascer- 
tained that  in  certain  regions  they  are  sensible  at 
from  10,000  to  12,000  feet  from  the  surface.  It  is 
certain,  however,  that  their  course  is  less  violent  in 
proportion  to  their  depth ;  and  in  the  deepest  recesses 
of  the  ocean,  if  any  movement  could  be  supposed  to 


A  REGION  OF  PERFECT  STILLNESS.  85 

exist,  it  would  be  insensible.  Thbre  is  a  region,  o) 
which  we  cannot  define  the  limits,  which  enjoys  » 
perfect  calm,  and  if  any  displacement  occurs  it  is 
that  which  results  from  slow  and  imperceptible 
molecular  motion.  The  temperature  of  that  region 
is  very  nearly  the  same  over  all  parts  of  the  globe, 
and  its  ^altness  is  considerable.  There  also  reigns 
the  most  profound  obsturity  ;  and  life,  constrained  in 
its  development  by  the  absence  of  light,  the  insuffi- 
cient supply  of  oxygen,  and  the  great  quantity  of 
carbonic  acid  contained  in  the  water,  ceases  at  last 
altogether,  probably  as  it  does  in  the  aerial  atmo- 
sphere at  a  height  exceeding  26,000  feet.  The  study 
of  that  calm  and  perhaps  lifeless  region  is  not, 
however,  uninteresting.  By  means  of  soundings  we 
are  able  to  ascertain,  in  some  measure,  what  is 
passing  there ;  and  if  we  avail  ourselves  of  these 
facts,  aided  by  the  science  of  the  geologist,  it  will 
not  be  difficult  to  infer  from  them  some  curious  de- 
tails concerning  the  history  of  the  globe. 


86  THE  BOTTOM  OF  THE  SEA. 


DEPOSITS  IN  COURSE  OF  FORMATION  AT  THE 
BOTTOMS  OF  SEAS. 


1.  Universality  of  the  process  of  Sedimentation — General  view  of 
the  Mechanism  of  this  Phenomenon. 

From  the  solid  rock  to  the  smallest  particle  of  slime, 
from  the  monstrous  whale  to  the  microscropic  infu- 
soriae,  from  the  algae  and  the  polypus  to  the  tower- 
ing denizen  of  the  forest  and  the  bird  which  hovers 
high  above  it  in  the  air,  the  Geogenic  Basin  (a  term 
which  will  be  presently  explained)  absorbs  all.  The 
work  of  sedimentation  is  universal. 

In  order  the  better  to  comprehend  this  pheno- 
menon we  will  follow  it  through  some  of  its  various 
phases.  The  rock  which  forms  the  culminating- 
point  of  the  highest  mountains  flies  into  splinters 
when  subjected,  as  in  winter,  to  sudden  changes  of 
temperature ;  or,  if  not,  it  yields  slowly  to  the  con- 
stant action  of  atmospheric  agencies,  and,  broken 
up  by  continually  increasing  fissures,  rolls  its  debris 
into  the  bed  of  a  torrent.  The  troubled  water 
breaks  fuiiously  against  the  obstruction,  and  grinds 


SEDT31 ES  TA  TION.  87 

the  fragments  to  pieces  one  against  another.  On 
reaching  the  phiins,  these  broken  and  partially- 
rounded  pieces  are  washed  into  the  comparatively 
quiet  current  of  a  river,  and  in  course  of  time,  by 
the  constant  motion  of  the  water  and  the  attrition 
caused  by  it,  assume  the  character  of  pebbles.  The 
river  slowly  carries  the  pebbles  towards  the  sea,  and 
all  the  time  their  size  is  diminishing.  Instead  of 
pebbles  they  become  gravel ;  the  particles  of  gravel, 
still  diminishing  in  size,  become  sand  ;  and  the  sand 
— more  especially  if  the  river  be  of  any  considerable 
width — tends  to  choke  its  bed.  The  remedial  action 
of  the  river  is  to  carry  the  sand,  and  the  broken 
earth  washed  from  its  banks,  down  to  the  sea,  where 
it  deposits  them,  at  a  distance  more  or  less  great 
from  its  embouchure,  according  to  the  weight  or 
tenuity  of  the  particles  and  the  strength  of  the  cur- 
rent. Finally,  the  smaller  stones  are  thrown  upon 
the  shore,  the  sands  are  deposited  farther  off  in 
the  sea,  and  the  light  mud  is  carried  away  and 
slowly  deposited  at  a  still  greater  distance.  The 
muddy  water  of  the  Amazon  is  distinguishable  at 
sea  nearly  a  hundred  miles  from  the  embouchure 
of  the  river. 

The  rocks  of  the  seashore  also  yield  their  tribute 
to  the  bottom  of  the  sea,  and  assist  very  materially 
to  fill  up  the  deeper  abysses,  the  slow  and  continual 


88  THE  BOTTOM  OF  THE  SEA. 

rising  of  which  must  seriously  modify  the  aspect  of 
our  globe.  Stormed  without  ceasing  by  the  waves, 
the  most  iron-bound  coast  must  gradually  give  way, 
but  with  results  which  vary  according  to  the  nature 
and  formation  of  the  coast-line. 

The  heavier  debris  is  naturally  disposed  to  con- 
tinue its  descent  till  it  reaches  the  greatest  depths. 
The  action  of  gravitation  is,  in  this  respect,  favoured 
by  the  action  of  the  currents.  We  have  explained 
in  a  previous  chapter  that  the  crust  of  the  globe  is, 
so  to  speak,  ploughed  up  in  furrows,  the  sides  of 
which  combine  to  form  basins  or  cavities  which  are 
separated  from  each  other  by  ridges  of  rock  more  or 
less  sharply  set.  In  geographical  science  these  fur- 
rows are,  one  and  all,  regarded  as  the  basins  of  rivers. 
The  waters  flowing  in  them  naturally  tend  to  the 
lower  parts,  and  in  those  lower  parts  they  combine 
to  form  perhaps  a  single  current.  This  current  flows 
down  to  a  still  lower  level — that  of  the  sea.  Nor 
even  here  does  the  conformation  lose  its  character 
of  a  furrow  or  basin.  We  follow  it  under  the  sea 
until  we  have  descended  so  deep  that  we  seem  to 
have  reached  a  central  point  from  which  it  is  impos- 
sible to  advance  in  any  direction  without  reascend- 
ing.  Using  this  lowest  point  as  a  centre,  we  draw  a 
line  around  it  at  a  greater  or  less  distance,  and  that 
line  indicates  the  circumference  of  what  we  have 


WEAIilXG  AWAY  OF  THE  COASTS.  K9 

called   a    geogenic   hasin,  to  distinguish    it   from   a 
geographic  basin. 

Thus,  the  basins  of  the  Rhone,  the  Ebro,  tiie 
Arno,  the  Tiber,  and  several  other  rivers,  all  com- 
bine to  form  one  vast  geogenic  basin.  The  Tyrrlie- 
nian  Sea  is  one  of  the  divisions  of  this  great  basin, 
the  Gulf  of  Lyons  is  another,  that  of  Genoa  a  third. 

2,  Action  of  Waves  upon  tlifi  Coasts — Destruction  of  Rock-bound 
Shores  by  the  Sea — Pierced  Rocks — Siltiiig-up  of  Shallow 
Waters  by  Marine  Alluvium. 

In  the  case  of  a  steep  shore  the  erosive  action  of 
the  sea  is  considerable.  It  beats  against  the  rocky 
barrier  with  all  its  force.  The  base  of  the  clifif,  in- 
cessantly attacked  by  the  waves,  is  of  course  eaten 
away  with  a  rapidity  proportioned  to  the  ease  with 
which  the  matter  of  the  rock  can  be  disintegrated. 
The  upper  part  of  the  cliff,  though  not  subjected 
to  the  direct  action  of  the  waves,  falls  forward,  and 
occasionally  forms  deep  rocky  caverns  such  as  we 
see  at  Bonifacio.  At  length  the  superincumbent  and 
tottering  mass  falls  into  the  sea.  If  the  depth  be 
great,  or  the  current  strong,  the  accumulated  debris 
is  swept  away,  and  the  action  of  the  waves  against 
the  broken  cliff  is  continued  with  undiminished  in- 
tensity. In  this  manner  entire  promontories  have 
been  destroyed ;  even  within  the  historic  period,  the 


90 


THE  BOTTOM  OF  THE  SEA. 


Straits  of  Gibraltar  have  been  enlarged  by  this  pro- 
cess. If,  on  the  other  hand,  the  depth  be  slight  at 
the  base  of  the  cliff,  the  force  of  the  waves  is  broken 
by  the  opposing  rampart  of  fallen  stones,  the  shore 
is  preserved  from  destruction,  and  it  is  only  at  some 


Fig.  17  — Waves  breaking  against  a  Rock-bound  Coast. 

distance  from  the  self-formed  talus  that  the  rolled 
stones  are,  in  the  course  of  ages,  carried  away  by  the 
currents  of  the  ocean. 

The  foot  of  the  cliff  marks  the  level  of  the  sea. 
If  this  level  be  changed  from  any  cause,  the  cliff  will 


FOHMATION  OF  CAVERNS.  91 

be  formed  anew  in  accordance  with  it.  In  seas  of 
little  extent,  such  as  the  Mediterranean  or  Caspian, 
and  at  those  points  of  the  ocean  where  the  tidal 
elevation  is  but  small,  the  cliff  will  consist  of  but 
one  simple  escarpment.  When,  however,  tlie  differ- 
ence between  the  level  of  high  and  low  water  is 
considerable,  as  in  the  English  Cliannel  and  other 
narrow  passages,  there  will  be  found  a  second  cliff 
corresponding  with  the  level  of  low-water. 

Many  marine  caverns  have  been  formed  by  the 
erosive  action  of  the  sea  upon  massive  beds  of 
basalt.  This  rock  is  the  product  of  ancient  volcanic 
eruptions,  the  volcanic  matter  having  separated 
itself  into  prismatic  columns  in  the  process  of  cool- 
ing. The  sea,  by  its  reiterated  assaults  through 
a  long  lapse  of  time,  causes  the  low^er  beds  of  basalt, 
which  are  the  most  exposed  to  the  fury  of  the  waves, 
to  yield  first.  Thus  are  formed  caves,  or  sometimes 
extended  galleries  and  halls,  of  which  the  Cave  of 
Fingal  is  a  beautiful  example. 

The  erosive  action  of  waves  is  slower  when  the 
rock  is  in  horizontal  beds.  In  such  cases  the  water 
rolls  over  the  inclined  surface  until  its  course  is 
arrested,  and  in  its  return  it  breaks  the  force  of  the 
next  approaching  wave. 

A  striking  effect  of  the  erosive  action  of  the  sea  is 
shown  in  the  phenomenon,  so  frequently  met  with,  of 


92  THE  BOTTOM  OF  TEE  SEA. 

pierced  rocks.  Sometimes  they  are  found  isolated 
in  mid-ocean  ;  sometimes  they  are  united  to  the  land, 
or  only  separated  by  narrow,  and  perhaps  tortuous, 
channels.  Let  us  hear  what  M.  de  Tessan  has  to 
say,  in  the  work  already  quoted,  of  the  manner  in 
which  waves  act  upon  such  rocks : — 

«Lat.  25°  0-9'  K;  long.  120°  76'  W.— We  have 
passed  very  near  the  Alijos  Kocks,  which  are  still 
marked  as  doubtful  in  some  charts.  The  highest  of 
them  rises  about  150  feet  above  the  sea.  It  is 
pierced  through  in  the  direction  from  south-east  to 
north-west.  This  phenomenon  of  pierced  rocks  oc- 
curs most  often  when  the  rocks  are  composed  of 
superimposed  beds,  of  no  great  thickness,  and  not 
well  compacted  one  with  another.  It  is  to  be  ex- 
plained by  the  action  of  the  billows ;  in  fact,  their 
most  destructive  effect  is  produced  upon  the  perpen- 
dicular face  of  the  rock,  about  the  middle  of  its 
elevation,  and  in  the  direction  in  which  the  waves 
strike  against  it.  The  rock  of  course  has  a  tendency 
to  crumble  away  at  that  point  more  than  elsewhere, 
and  if  its  composition  be  such  that  it  cannot  resist 
the  incessant  shock  of  the  waves,  an  excavation 
necessarily  results.  The  hollow,  once  formed,  be- 
comes itself  the  cause  of  an  increased  destructive 
effect  on  the  action  of  the  waves.  Gliding  along 
the  sides   of  the   excavation,  they  strike  with  re- 


riEIiCED  ItOCICS.       Vl*^      <S^       03 

doubled  speed  upon  its  bottom,  wherS^J^Jr/oMaj^ 
debris  of  the  rock,  dashed  about  with  imme^e^rce, 
helps  also  to  break   up   the  rock  and  make  fresh 
debris.     In  this  way  the  deptli  of  the  excavatiou 
increases,  its  sides  are  enlarged,  and  at  last  dayliglit 


Fig.  18. —  liocks  worn  through  by  Uje  Waves. 


is  let  in  from  the  other  side.  To  produce  this  result, 
however,  the  rock  must  not  be  too  thick,  because 
there  is  obviously  a  limit  m  the  depth  of  the  exca- 
vation at  whi^ih  the  wave  loses  its  force" 


94  THE  BOTTOM  OF  THE  SEA. 

If  the  sea  struggles  victoriously  against  the  laud 
when  the  latter  opposes  to  it  some  formidable  ob- 
stacle, its  efforts  fail,  its  force,  so  to  speak,  expires 
when  there  is  no  such  resistance.  It  batters  down 
the  rock-bound  shore  with  resistless  force ;  it  flows 
harmlessly  over  low  and  sandy  flats.  Further,  the 
debris  of  the  stubborn  rock  serves  to  strengthen  the 
shifting  sands,  and  to  renew  the  dunes  which  the 
winds  scatter  in  light  clouds  of  dust.  The  tidal  wave 
spreads  out  over  the  level  shore,  until  it  has  lost 
all  its  speed,  and  when  it  retires  it  leaves  behind  it 
on  the  sands  all  the  materials  which  it  had  pushed 
before  it  as  it  came  in  from  the  sea. 


3.  Deposits  in  Mid-ocean,  and  Deposits  on  the  Coasts — Importance 
to  Geologists  of  Coast  Deposits  as  data  for  fixing  the  limits  of 
Ancient  Seas — Deposits  of  the  French  Seas. 

It  is  only  from  a  large  number  of  skilful  soundings 
that  we  have  been  able  to  ascertain  the  character  ot 
submarine  deposits.  Soundings  at  great  depths 
generally  indicate  the  presence  of  the  debris  of  rocks 
in  a  state  of  minute  subdivision.  To  take  a  single 
example :  at  a  point  seventy  leagues  south  of  the 
Aleutian  Isles,  and  at  a  depth  of  9000  feet,  we  detect 
the  presence  of  fine  sand  and  mud. 

The  deeper  parts  of  the  ocean  occur  at  too  great 
a  distance  from  the  coasts  for  the  larger  and  heavier 


DEPOSnS  IN  DEEP  WATER.  95 

eubstances  to  be  carried  down  into  those  profound 
gnlfe  by  the  marine  currents.  If  the  remains  of 
animals  and  plants  fall  directly  from  the  surface 
into  such  depths,  they  preserve  their  forms,  however 
delicate,  because  the  calm  which  reigns  in  these  still, 
mysterious  regions  allows  them  to  rest  undisturbed 
for  an  indefinite  period  in  the  spot  they  first  touch. 
Thus  the  accumulation  of  materials  is  a  slow  and 
gentle  process.  They  repose  quietly  in  horizontal 
and  homogeneous  beds,  and,  as  a  consequence,  produce 
compact  and  finely-grainel  rocks. 

On  the  coasts,  and  in  those  parts  of  the  sea  which 
are  of  slight  depth,  we  generally  find  stones  and 
bodies  too  large  to  be  carried  away  by  the  currents. 
The  materials  thus  accumulated  are  subjected  to  the 
continual  action  of  the  water.  They  lose  their  angles, 
and  become  rounded  or  oval  in  form.  They  are  in- 
cessantly worn  away  and  incessantly  renewed.  The 
result  is  that  coast  deposits  have  neither  the  same 
regularity  nor  the  same  consistency  as  those  of  the 
deeper  seas.  They  do  not  exhibit,  like  the  latter,  a 
compact  structure,  nor  do  the  substances  which  com- 
pose them  display  sharp  angles  and  well-preserved 
forms. 

The  action  of  the  waves  extends  to  an  inconsider- 
able depth  from  the  surface,  especially  in  all  ordinary 
times  when    there  is    no  extreme   aj^itation.      The 


56  THE  BOTTOM  OF  TEE  SEA. 

littoral  deposits  are,  therefore,  of  comparatively 
slight  amount  when  regarded  as  to  their  quantity 
merely,  but  theoretically  they  are  of  the  greatest 
importance.  An  exact  knowledge  of  their  character 
often  enables  the  physicist  to  determine  the  oscilla- 
tions of  the  sea,  how  it  has  retired  from  the  land  or 
encroached  upon  it,  and  consequently  to  what  extent 
the  terrestrial  crust  has  been  affected.  The  follow- 
ing details  are  borrowed  from  a  work  presented  to 
the  French  Institute,  some  two  years  ago,  by  M. 
IJelesse,  and  which  may  be  described  as  a  complete 
study  of  the  deposits  which  are  being  formed  in 
our  time  upon  the  coasts  of  France,  and  of  the  re- 
lations they  bear  to  currents  and  marine  animals, 
but  more  particularly  to  the  nature  of  the  rocks 
which  form  the  shore. 

This  littoral  deposit  presents  a  mineralogic  com- 
position of  considerable  variety  at  a  level  corres- 
ponding to  that  of  high-tide,  because  it  includes  the 
debris  of  the  neighbouring  cliffs.  At  the  level  of 
low  tide,  on  the  shores  of  the  Ocean,  it  is  much  more 
uniform,  and  even  exhibits  a  constant  character  to  a 
great  extent.  Where  we  find  this  to  be  the  case,  we 
may  be  sure  that,  whatever  be  the  character  of  the 
rocks  which  concur  to  form  the  deposit,  the  sea  is 
not  slow  to  destroy  them.  The  minerals  we  dis- 
cover are  those  which  offer  considerable  resistance  to 


LfTTORAL  DEPOSITS.  97 

the  action  of  the  sea,  owing  to  their  hardness  or  the. 
unalterable  nature  of  their  composition. 

The  most  common  of  all  minerals  in  the  littoral 
deposit  of  France,  at  the  level  of  low-tide,  is  trans- 
parent quartz.  It  is  distributed  in  such  profusion 
that  the  deposit  is  sometimes  almost  entirely  com- 
posed of  it.  This  is  to  be  accounted  for  by  its 
extreme  hardness  and  its  abundance  in  the  cliffs. 

The  clays  are  found  in  the  deposit  at  the  bottom 
of  gulfs  and  retired  creeks ;  tliey  are  carried  away 
in  the  form  of  mud,  and  settle  down  when  the  sea:  is 
calm  and  deep.  In  some  cases  where  beds  of  clay 
or  schist  abound  on  a  coast  (as  at  Honfleur),  the  pro- 
portion of  clay  contained  in  the  littoral  deposit  is 
very  great. 

Carbonate  of  lime  or  chalk  is  found  in  very 
variable  proportions,  and  is  derived  from  calcareous 
rocks  and  the  remaias  of  molluscs.  In  the  Mediter- 
ranean it  is  most  abundant  when  the  cliffs  are  com- 
posed of  calcareous  rock,  as  at  Nice  and  Marseilles. 
Its  fragments  are  always  well-rounded.  On  the  shores 
of  the  Ocean,  the  littoral  deposit  of  lime  is  small, 
because  the  movement  caused  by  the  tides  dissolves 
and  disposes  of  it  very  rapidly  even  when  it  is  strong 
or  compact.  An  instance  of  this  may  be  observed 
between  Havre  and  Dunkirk,  or,  better  still,  at 
the  foot  of  the  Lower  Pyrenees.   It  may  even  happen 

H 


98  THE  BOTTOM  OF  THE  SEA. 

that  the  deposit  formed  on  a  chalky  shore  does  not 
contain  a  trace  of  calcareous  debris.  On  the  Atlantic 
coasts  of  France  the  carbonate  of  lime  found  in  the 
littoral  deposit  comes  almost  entirely  from  the  shells 
of  molluscs  of  the  existing  period.  It  is  composed 
of  angular  or  slightly-rounded  fragments,  and  it 
resists  destruction  much  better  than  the  most  com- 
pact limestone.  On  the  other  hand,  we  may  see  a 
coast  without  limestone,  like  that  of  Brittany,  present 
nevertheless  a  rich  littoral  deposit  of  carbonate  of 
lime,  exclusively  derived  from  the  debris  of  shells. 

As  we  proceed  to  a  distance  from  the  shore,  the 
depth  of  the  water  increases,  and  the  marine  deposit 
changes  its  physical  and  chemical  properties.  Thus, 
the  proportion  of  carbonate  of  lime  grows  larger,  and 
its  particles  at  the  same  time  diminish  in  size.  On  the 
whole,  these  researches  demonstrate  that  the  littoral 
deposit  varies  in  its  character  with  the  hydrographic 
basin  to  which  it  appertains,  and  with  the  coasts, 
above  and  below  the  water,  upon  which  it  is  formed ; 
in  the  Ocean,  on  'the  contrary,  it  remains  pretty  con- 
stantl}^  the  same  over  a  vast  extent  of  surface.* 

*  Delesse :  Beclierches  sur  le  depot  littoral  de  la  France  (Comptes 
Rendus  de  I'lnsstitut  de  Frauce,  Number  for  January  2S,  18G7, 
pp.  165  et  seq.) 


DEBRTS  OF  GLACIERS.  90 

4.  Transport  and  Deposit  of  Rocks  by  Floating  Ice. 

When  fragments  of  rock  are  transported  by  the 
water,  it  carries  the  smaller  and  lighter  sand  to  a 
greater  distance  than  the  heavier,  this  again  to  a 
greater  distance  than  stones  or  pebbles,  and  these 
latter,  of  course,  much  farther  than  great  blocks  of 
stone.  These  materials  of  the  earth's  crust  find  also 
a  powerful  and  majestic  means  of  transport  in  floating 
ice;  but  it  carries  its  load  without  discrimination, 
and  deposits  fragments  of  all  sizes  and  of  every  de- 
scription that  may  chance  to  be  imbedded  in  its 
mass.  During  winter  we  see  our  rivers  covered  with 
a  sheet  of  ice :  the  spring  returns,  the  frozen  surface 
is  melted,  and  masses  of  ice  float  seaward  in  dis- 
ordered heaps.  This  phenomenon  constitutes  an 
annual  break-up.  Where  the  water  touches  the  shore 
stones  and  earth  become  imbedded  in  its  solidified 
mass.  If  the  river  be  completely  frozen  in  its  whole 
depth  (which  happens  sometimes  in  northern  coun- 
tries), its  bed  as  well  as  its  shores  will  load  the  ice  with 
debris,  which  is  thus  transported  to  a  distance. 

This  phenomenon,  which  we  witness  once  a  year,  is 
produced  on  a  grand  scale  in  the  polar  seas.  On 
those  inhospitable  shores  the  rivers  of  ice,  called 
glaciers,  glide  down  from  mountain  heights  into  the 
.sea,  and  carry  on  their  surface,  as  well  as  m  their 


100 


THE  BOTTOM  OF  THE  SEA, 


interior,  massive  fragments  of  rock,  gravel,  and  dirt. 
Sometimes  a  mass  is  detached  from  the  glacier,  and, 
floating  away  into  the  open  sea,  is  impelled  by  the 
marine  currents  and  the  winds  towards  the  equator. 
On  the  passage,  the  shock  of  one  such  mass  striking 
against  another,  the  action  of  the  waves,  and  the 
melting  of  the  surface  of  the  ice,  destroy  the  mass, 


V\g.  19. — Section  of  the  Sea  and  the  Sea-bottom  in  the  Track  of  Icehcrgs 
between  Gieenlaud  and  Newfoundland. 

and  the  debris  which  it  carries  drops  from  time  to 
time  to  the  bottom  of  the  water.  In  this  manner, 
icebergs  perform  their  part  in  the  work  of  sedi- 
mentation 

The  deposits  formed  by  icebergs  attain  in  course 
of  time  to  a  great  tliickness  The  Bank  of  New- 
foundland appears  to  have  been  formed  in  this  way. 


POLAR  IGK' FIELDS.  101 

Every  year  the  cold  currents  flowing  from  Baffin's 
Bay  (which  in  strictness  should  be  called  a  sea)  visit 
Newfoundland  with  their  imposing  freight  of  ice- 
fields and  frozen  mountains.  On  approaching  that 
island  they  encounter  the  Gulf  Stream,  and  the 
frozen  masses  gradually  disappear,  being  eaten  away 
by  the  waters,  the  heat  of  which  undermines  them. 
The  earth  and  fragments  of  rock  which  they  carry  fall 
to  the  bottom  of  the  sea. 

Every  year  the  warmer  current  of  the  Gulf  Stream 
arrests  these  masses  of  ice  at  the  same  point  of  their 
track,  and  causes  them  to  break  up  and  disappear. 
A  simple  current  of  water  opposes  to  them  an  im- 
passable barrier.  The  debris  accumulates  year  after 
year  in  the  neighbourhood  of  Newfoundland  without 
ever  entering  into  the  Mexican  current.  What  ages 
must  it  have  required  for  this  submarine  de})osit  to 
have  filled  up  an  abyss  to  a  height  of  from  20,000  to 
30,000  feet! 

Thus  the  influence  of  the  polar  ice-fields  is  so 
great  as  to  modify,  in  course  of  time,  the  form  of  the 
earth's  surface.  This  too  occurs  over  a  large  ex- 
tent of  the  globe,  seeing  that  the  ice  in  the  northern 
hemisphere  actually  attains  to  the  40th  degree  of 
latitude,  and  in  the  southern  hemisphere  to  the 
30th  degree. 


102  THE  BOTTOM  OF  THE  SEA 

i).  Water-spi ings  in  the  Earth — Funnels  or  Wells  of  the  Jura— 
The  Aveii  of  the  South  of  France — Katavotron — Sinkholes — 
Geysers — Submarine  Springs — Origin  of  Oolitic  Formations. 

Water  spread  on  the  earth  penetrates  to  a  certain 
distance  below  the  surface.  It  sinks  through  sandy 
places,  cultivated  lands  of  all  kinds,  and  even  through 
the  hardest  rocks.  Fissures  are  produced  in  the 
latter  by  the  influence  of  temperature,  and  by  these 
little  channels  the  water  descends  into  the  interior  of 
the  earth's  crust.  Limestones  favour  a  cavernous 
structure,  and  conceal  gulfs  or  pits  which  are  known 
by  different  names  in  different  countries.  These  are  the 
Funnels  or  Wells  of  the  Jura,  the  Sinkholes  of  America, 
the  Katavotron  of  Greece,  and  the  Aveu  of  the  South 
of  France.  Such  gulfs  may  sometimes  be  found  in 
the  course  of  rivers.  In  a  word,  by  whatever  means 
of  absorption,  the  water  finds  its  way  into  the  ter- 
restrial crust,  and  that  to  a  very  considerable  extent. 
After  an  interval,  more  or  less  prolonged,  it  returns 
to  the  surface.  Springs,  fountains,  artesian- wells, 
geysers,  are  thus  originated.  Geysers  are  intermittent 
springs  of  boiling  water,  observed  for  the  first  time 
in  Iceland,  where  the  phenomenon  is  attended  by 
remarkable  circumstances.* 

The  return  of  the  water  to  the  surface  takes  place 

*  See  "  Iceland :  its  Scenes  and  Sagas,"  by  S.  Baring-GouJd. 


SUBMARINE  SPRINGS.  103 

ander  tne  sea  no  less  than  on  continents,  as  proved 
by  numerous  observations  of  submarine  springs  of 
fresh-water.  Many  such  have  been  remarked  on  the 
Mediterranean  littoral.  According  to  M.  de  Ville- 
neuve-Flayosc,  those  which  we  find  between  Perpig- 
nan  and  Spezzia,  at  a  distance  more  or  less  great  from 


Fig.  20. —Cause  of  Submanne  Sprinors.  {aa)  Sea  Water;  (bb)  Fresh 
Waler;  (cc)  Impeimeable  Stratji ,  (dd)  a  Permeable  Stratum  in  which 
the  Fresh  Water  flows. 


the  shore,  deliver  some  50  cubic  metres  every  second, 
which  is  about  one-third  of  the  quantity  of  water 
delivered  by  the  Seine  in  the  same  time. 

In  the  Gulf  of  Spezzia,  at  the  distance  of  60  or 
70  yards  from  the  shore,  we  see  a  kind  of  swelling 
in  the  sea*  it  extends  over  a  space  about  80  feet 


lOi  THE  BOTTOM  OF  THE  SEA 

in  diameter,  and  is  something  less  than  six  inches  in 
height.  When  the  sea  is  calm  it  is  easy  to  see  ver- 
tical jets  of  water  springing  from  the  bottom.  This 
water  is  found  to  be  fresh,  and  it  comes  from  a  sub- 
marine spring.  Its  superior  lightness  causes  it  to 
reach  the  surface  of  the  sea  before  the  salt-water  has 
time  to  aifect  it. 

At  some  distance  from  the  embouchure  of  the  Ga- 
laso,  in  the  Gulf  of  Tarentura,  there  springs  from  the 
bottom  of  the  sea  a  jet  of  fresh-water  so  powerful 
that  it  can  be  procured  without  mixture  with  the  salt- 
water. A  similar  jet  exists  in  the  famous  salt-pool 
of  Thau,  near  Cette  (on  the  Mediterranean  coast  of 
France)  ;  here  the  fresh-water  rises  so  rapidly  that  it 
produces  waves. 

What  may  be  called  a  true  subterranean  river  de- 
bouches under  the  sea  near  Ragusa.  There  are  sweet- 
water  springs  in  the  ports  of  Cattaro  and  Aulona, 
near  the  embouchure  of  the  Acheron,  in  the  midst  of 
the  sea ;  over  a  space  of  40  feet  in  diameter  fresh- water 
is  thrown  up  abundantly  with  great  force.  This  is 
probably  the  same  spring  of  which  Pausanias  speaks. 

A  stream  of  fresh-water  springs  from  the  bottom 
of  the  sea  near  Tortosa,  on  the  coast  of  Syria.  Its 
force  is  so  great  that  the  sweet  water  can  be  taken 
without  mixture  with  the  salt.  Pliny  speaks  of  a 
similar  phenomenon  near  Arcadus. 


SUBMAlilNE  J3PR1NGS.  105 

The  Gulf  of  Argos  supplies  an  example  of  a  very 
abundant  source  of  fresh-water  named  Anavolco,  and 
situate!  between  Kiveri  and  Astros.  Ancient  writers 
affirm,  though  this  may  be  a  little  uncertain,  that  it 
has  been  in  activity  some  1700  years.  Colonel 
Leake,  a  traveller  remarkable  for  his  minute  observa- 
tion, informs  us  that  the  column  of  fresh-water 
appears  to  be  not  less  than  50  feet  in  diameter. 
When  the  atmosphere  was  calm  he  observed  that  the 
water  rose  with  such  force  from  the  bottom  of  the  sea 
as  to  swell  the  surface,  and  agitate  it  in  concentric 
circles  to  a  distance  of  some  hundreds  of  feet.  He 
attributed  this  to  the  embouchure  of  a  subterranean 
river  at  the  bottom  of  the  sea. 

This  phenomenon  may,  in  a  certain  measure,  be 
compared  with  that  of  artesian- wells,  now  so  familiar 
to  us.  The  water  finds  its  way  into  the  earth  by  fil- 
tration through  certain  permeable  strata.  These  are 
so  enclosed  by  beds  of  clay,  or  other  matters  not  per- 
meable, that  they  form  conduits  which  accidentally 
terminate  beneath  the  sea.  The  fresh-water  running 
in  these  natural  conduits  is  lighter  than  saltr water. 
If  it  exists  in  sufficient  quantity  to  prevent  its  being 
mixed  completely  with  the  latter,  it  rises  to  the  sur- 
face on  the  same  principle  that  oil  floats  on  the 
surface  of  ordinaiy  water. 

It  is  not  surprising,  therefore,  that  we  should  find 


106  THE  BOTTOM  OF  TEE  SEA. 

in  all  seas  submarine  springs  of  fresh-water.  Hum- 
boldt observed  one,  two  or  three  leagues  southward 
from  Cuba,  rising  with  such  force  that  the  smaller 
craft  could  not  approach  without  risk.  Ships  supply 
themselves  with  this  water,  and  find  it  sweeter  than 
water  taken  from  other  places  of  greater  depth. 

Water  that  has  been  in  the  earth  holds  in  solution 
a  certain  amount  of  salts,  proportioned  to  the  time  it 
has  been  detained  underground,  and  to  the  depth 
and  consequently  increased  temperature  it  may  have 
attained.  On  returning  to  the  surface,  whether  it  be 
on  the  land  or  beneath  the  sea,  it  makes  some  slight 
deposit  of  the  salt  it  holds  in  solution.  Of  course  the 
quantity  is  not  greater  than  is  usually  to  be  lound  in 
what  is  called  fresh-water,  yet  the  deposit,  accumu- 
lated-..through  a  long  period  of  time,  assists  in  the 
work  of  sedimentation,  and  thus  modifies  the  bottom 
of  the  sea.  To  express  by  one  word  the  character  in 
common  of  all  the  deposits  thus  formed,  they  may 
be  called  "Geyserian."  Tliis  appellation  has  been 
given  to  them  by  M.  Alexandre  Yezian,  from  the 
phenomenon  which  may  be  considered  typical. 

Springs  charged  with  stony  matter,  that  is  to  say, 
petrifying  springs,  are  the  cause  of  deposits  after 
their  kind,  but  differing  considerably  according  as 
the  water  in  which  they  rise  is  calm  or  troubled.  In 
the  first  case,  the  deposit  is  made  tranquilly,  and  the 


OOLITIC  ROCKS.  107 

result  is  a  compact  and  homogeneous  rock.  Wlien, 
however,  the  water  thus  charged  rises  from  a  slight 
depth,  or  at  a  point  where  it  is  subjected  to  tlie  in- 
fluence of  marine  currents,  the  matters  already  de- 
posited are  so  tossed  about  that  they  present  all 
their  surfaces  to  the  petrifying  action.  The  in- 
crustation thus  caused  deposits  itself  all  around  them 
in  concentric  layers ;  and  their  final  combination,  or 
massing  together,  causes  them  to  resemble  a  heap  of 
little  eggs.  The  aggregation  of  all  these  oolitic  par- 
ticles by  the  incrusting  matter  does  not  completely 
deprive  the  deposit  so  formed  of  its  primitive  cha- 
racter, and  it  is  accordingly  named  oolite  (or  stone 
formed  of  eggs).  The  structure  of  this  kind  of  rock 
has  been  called  by  geologists,  Oolitic. 

The  submarine  deposits  resulting  from  Geyserian 
action  are  of  much  less  importance  than  those  which 
are  due  to  mechanical  sedimentation.  The  physical 
forces  play  only  a  special  part  in  their  production. 
The  life  of  the  globe  is  the  cause  of  numerous  mo- 
difications in  the  aspect  of  the  submarine  soil,  and 
in  the  nature  of  the  deposits  which  accumulate  at 
the  bottom  of  the  Ocean.  Independently  of  the  re- 
mains of  terrestrial  animals  and  plants  which  are 
borne  into  the  sea,  and  swept  through  its  depths  by 
marine  currents,  or  rolled  by  the  waves,  innumerable 
creatures  live  in  the  sea  itself,  and   enric^h  it  witli 


108  THE  BOTTOM  OF  THE  SEA. 

their  spoils.  A  rapid  study  of  these  beings  is  indis- 
pensable to  whomsoever  would  form  an  accurate  idea 
of  the  submerged  portion  of  the  earth's  crust,  and  of 
the  phenomena  which  are  produced  on  that  w  onderiiil 
stage  of  animate  and  inanimate  existence. 


1"0 


SUBMARINE  LIFE. 


1  Mxuboraiice  of  Life  in  the  Deptlis  of  the  Ocean — Tableau  of  the 
Tropical  Seas — Life  in  the  Seas  of  the  Tenipemteand  the  Frozen 
Zones — Natural  Illumination  of  the  Ocejinic  Abysses. 

Shall  we  say  the  play  of  life  is  pleasing  to  the 
J)eity  ?  Everywhere  we  see,  or  we  sensate,  that  great 
and  incomprehensible  manifestation  of  His  omnipo- 
tence. Myriads  of  animals  and  plants  people  the 
earth  and  the  air  with  forms  of  grace  and  beauty ; 
but  in  no  part  does  the  creative  power  reveal  itself 
with  more  of  grandeur  and  magnificence  than  in  the 
abysses  of  Ocean.  There,  in  fact,  may  be  discovered 
the  principles  of  all  life.  In  the  inspired  account  of 
the  creation  we  are  told  that  "  in  the  beginning  "  the 
Spirit  of  God  '*  moved  upon  the  face  of  the  waters." 
The  surfacp  of  the  sea  is  less  varied  than  that  of  the 
dry  land ;  but  look  deep  into  its  bosom,  and  no  region 
of  the  earth  could  give  so  vivid  an  idea  of  the  exu- 
berance of  life.  Forms  the  most  unexpected,  a 
fecundity  the  most  marvellous,  challenge  our  admi- 
ration at  every  step  we  take  through  these  wonderfnl 
regions.  Here,  to  all  appearance,  is  a  planr,  aminia- 
tnre  tree  growing  upon  a  rock ;    its  branches   an* 


no  THE  lOTTOJi  OF  TRE  SEA. 

verdurelcss,  but,  strange  to  say,  flowers  of  the  most 
brilliant  colours  spiiiig  from  their  extremities.  The 
petals  have  the  po.ver  of  motion,  and  by  this  motion 
they  cause  a  miniature  current  to  flow  unceasingly 
towards  them.  T"^nhappy  are  the  animalculae  who 
may  be  drawn  into  this  perpetually  renewed  stream, 
for  it  flows  into  the  mouths  of  the  zoantharia,  or 
animal-flower  to  which  they  serve  for  food ! 

See ! — there  are  two  eyes  sparkling  in  the  sandy 
bottom.  A  living  form,  which  escaped  our  observa- 
tion before,  detaches  itself,  as  if  a  leaf  rose,  undu- 
lating in  the  water,  after  having  stirred  up  around  it 
a  cloud  of  sand  or  other  earthy  particles.  That 
living  form  is  a  turbot  or  a  sole.  At  the  least  hint 
of  danger  it  will  retreat  to  the  bottom,  and,  disposing 
itself  flat  upon  the  sand  or  mud,  become  almost  in- 
visible. This  ruse  is  the  only  mean^^  of  defence  pos- 
sessed by  these  creatures,  and  almost  any  other  fish 
is  bold  enough  to  make  them  its  prey.  It  is  worth 
noting  that  one  side  of  the  body  is  white,  the  other 
(on  which  the  eyes  are  placed)  is  greenish-brown, 
resembling  the  bottom  of  the  sea. 

And  that  bundle  of  serpents  in  violent  agit^ion 
at  the  entrance  of  an  ocean-cavern !  How  they 
twine  and  writhe  as  they  seize  upon  the  living  prey 
which  an  evil  destiny  draws  into  their  neighbourhood  ! 
Suddenly  they  launch  themselves  precipitately  out 


CIVPTLE-FISH.  Its 

of  their  darksome  retreat;  a  body  of  some  kind, 
armed  with  a  sharp  beak,  has  ehitohed  hold  of  the 
creature ;  two  enormous  eyes  light  the  march  of  a 
more  hideous  monster  than  imagination  ever  de- 
picted. But  a  gigantic  form  advances  rapidly  against 
it.  A  terrible  struggle  seems  imminent.  No !  the 
monster  with  the  long  arms  vomits  a  black  poison ; 
the  water  to  a  great  distance  around  it  is  filled  with 
a  dense  fog ;  the  enemy  retires,  and  the  poulpe  con- 
tinues to  hunt  his  prey  in  a  domain  which  few  ani- 
mals dare  approach. 

The  ungainly  bulk  of  the  various  kinds  of  whales ; 
the  elegant  forms  of  the  argonauta ;  the  crab  in  his 
coat-of-mail ;  the  sea-urchin,  which  one  would  with 
difficulty  recognise  for  an  animal  if  it  were  not  for 
the  singular  movement  of  his  spines  and  his  locomo- 
tive suckers;  the  innumerable  swarms  of  fish  which 
everywhere  fnrrow  the  ocean,  thicker  tlian  birds  and 
insects  wing  the  air ;  the  immense  shoals  of  medusae 
transported  by  the  marine  currents  like  clouds  of 
locusts  on  the  wings  of  the  wind — all  these  hosts  of 
the  sea,  after  all,  occupy  but  a  limited  region  in  its 
immense  extent. 

As  soon  as  we  descend  a  little  below  the  surface, 
what  interesting  species  and  elegant  forms  conceal 
themselves,  so  to  speak,  in  organisms  of  the  simplest 
character,  because  adapted  to  the  uniform  existence 

1 


n\  THE  BOTTOM  OF  THE  SEA. 

which  they  all  lead !  What  richness  raay  be  found 
in  that  relative  poverty ! — what  profusion  of  life  in 
those  abysses  to  which  we  have  not  even  access ! 

The  inhabitants  of  the  greatest  depths,  Jke  those 
of  the  greatest  heights,  are  the  most  uniformly  dis- 
tributed. Many  of  them  are  genuine  citizens  of  the 
world ;  others,  inhabiting  the  low  bottoms,  are  sepa- 
rated from  the  rest  of  the  world  by  the  deep  waters 
as  by  an  impassable  barrier.  It  is  near  the  common 
surface,  in  regions  swept  by  the  winds,  and  subject 
to  every  variety  of  temperature,  that  animals  exhibit 
those  diversities  of  character  which  fit  them  either  for 
tlie  torrid  zone,  or  the  frozen  regions  which  surround 
the  poles.  A  current  of  warm  water  is  as  effective  in 
keeping  the  distinct  faunae  apart  as  a  rampart  of 
flames.  The  Gulf  Stream  nourishes  beings  to  which 
the  neighbouring  waters  would  prove  fatal ;  while,  on 
the  other  hand,  its  own  genial  boundaries  are  impas- 
sable to  species  accustomed  to  the  cold  northern  seas. 

That  roving  giant,  the  whale,  hunts  in  cold  waters, 
and  we  never  encounter  him  except  he  is  in  pursuit 
of  a  shoal  of  herrings  or  other  small  fish,  of  which  he 
devours  whole  nations  at  once.  Throwing  his  vast  bulk 
upon  the  serried  ranks  of  his  feeble  enemy,  he  fills 
his  maw  with  legions  of  victims,  and  keeps  them 
» crowded  together  in  that  antechamber  of  death,  to 
devour  them  leisurely  one  by  one — his  contracted 


CLIMATES  OF  THE  SEA.  W 

swallow  setting  a  limit  to  his  enormous  appetite. 
The  cachalot  (spermaceti  whale)  finds  himself  at 
home  in  warm  regions,  and  there  disputes  the  empire 
of  the  sea  with  the  terrible  shark.  The  phoca  or 
sea-cow,  the  porpoise,  and  the  narwhal  leave  free 
CO  the  dolphin  the  equatorial  belt  of  waters,  and  fix 
tlieir  cantonments  in  colder  regions.  Often  they  fur- 
nish unhoped-for  resources  to  the  adventurous  wan- 
derer in  latitudes  covered  with  frost  and  snow. 

There  is  an  immense  difference  in  the  aspects 
respectively  of  warm  and  cold  seas.  The  actors  are 
not  the  same.  The  landscape  itself  presents  totally 
different  characters.  Numerous  plants  contribute 
their  gniceful  presence  to  adorn  the  hills  and  valleys, 
but  (as  we  observe  on  land),  they  are  not  the  same 
which  grace  the  heights  with  their  long  flexible  rib- 
bons, swept  by  the  currents,  and  which  constitute  the 
sea-green  meadows  in  the  calm  deeps  of  the  ocean. 
The  richest  vegetation  is  found  in  the  temperate 
zones.  There  flourish  immense  forests,  even  more 
mysterious  than  the  sacred  woods  of  olden  time. 
Fish,  molluscs,  crabs,  are  the  happy  denizens  of  these 
shady  retreats.  But  who  can  flatter  himself  that  lie 
is  familiar  with  these  haunts  ?  Do  they  not  rather 
seem  for  ever  closed  against  the  intrusion  of  man  ? 
Who  can  presume  to  fathom  the  mystery  of  these 
immense  tracts,  denser  with  foliage  than  the  virgin 


]I8  THE  ncr'WM  OF  THE  SEA. 

forests  of  the  New  World  ?  And  what  of  the  joys  and 
griefs,  the  struggles  and  massacres,  of  which,  if  the 
faint  conceptions  of  our  imagination  can  be  trusted, 
these  vast  wildernesses  may  be  the  scene  ? 

If  you  desire  an  illustration,  see  there,  among  the 
rank  herbage  and  flags  at  the  embouchure  of  that 
great  river,  an  animal  which  measures  anything  under 
eighteen  feet  from  the  head  to  the  extremity  of  the 
tail.  His  form  recalls  that  of  a  pentagonal  column 
or  a  log  of  w^ood.  He  is  squatting  there,  silent,  im- 
moveable. His  tremendous  jaws  have  an  almost- 
benignant  expression,  and  all  around  float  barbi lions, 
looking  like  little  worms.  What  a  prey  for  any  little 
fish  that  may  be  swimming  in  the  neighbourhood ! 
But  these  worms  are  under  the  guard  of  a  great 
monster.  The  little  fish  advances  in  haste  to  seize 
them.  The  benign  jaws  separate,  and  in  a  moment  he 
is  swallowed.  Perchance  he  makes  a  silent  vow  that 
lie  will  never  again  hunt  this  kind  of  prey ;  but  if  he 
has  been  this  time  the  sport  of  an  illusion,  has  he  not 
often  given  chase  to  worms  as  supple  and  as  frisky  ? 

The  w^orm  floats  in  the  water,  or  hollows  out  for 
itself  some  abode  in  the  fine  sand,  far  from  all  agita- 
tion. It  nourishes  itself  with  the  infinitely  little, 
but  sometimes  it  attaches  itself  to  great  animals,  at 
whose  expense  it  lives,  as  we  see  in  the  case  of  ter- 
restrial creatures.     Certain  species  attain  a  consider- 


FECUNDITY  OF  FISH.  lli» 

able  lengtL  Everywhere  they  encounter  voracioua 
enemies.  Pursued  into  tlie  pools,  tracked  in  the 
sands,  these  creatures  escape  annihilation  oaly  by 
their  extreme  fecundity. 

It  would  seem  as  if  Nature — in  the  greater 
number  of  beings  that  people  the  ocean — had 
sought  to  compensate  them  by  an  incredible  fe- 
cundity for  the  causes  of  destruction  by  which  they 
are  surrounded.  Some  fish  of  large  size  have  only 
two  or  three  young,  like  the  majority  of  terrestrial 
animals ;  but  what  shall  we  say  of  the  fertility  of 
the  herring,  the  mackerel,  the  cod,  the  sturgeon,  and 
other  inhabitants  of  the  seas?  It  has  been  calcu- 
lated that  if  a  herring  could  multi[)ly  during  twenty 
years  without  losing  any  of  its  spawn  or  fry,  its 
offspring  would  form  a  mass  ten  times  greater  than 
the  globe.  Obviously,  the  smaller  creatures  which 
are  destined  to  serve  as  food  to  these  enormous 
hosts  must  be  more  prolific  still ! 

As  we  advance  towards  the  equator,  vegetation 
becomes  less  abundant  and  less  varied.  Tiie  waters 
are  too  much  heated  to  be  agreeable  to  the  greater 
number  of  the  algae,  and  if  in  any  part  of  the 
equatorial  seas  the  submarine  vegetation  attains  the 
scale  of  grandeur,  it  is  still  wanting  in  the  delicacy 
and  elefifance  which  characterise  the  vegetation  of 
the  temperate  zones. 


120  THE  BOTTOM  OF  THE  SEA. 

Nor  are  the  frozen  regions  of  the  earth  more 
agreeable  to  the  algae  than  those  which  arc  too 
highly  heated.  They  disappear  long  before  we 
cease  to  find  traces  of  animal  life.  Flowers  pre- 
serve their  brilliance  under  the  snow,  which  pro- 
tects them  from  the  too  intense  cold ;  but  the 
polar  ice  does  not  seem  to  perform  a  similar  kind 
office  for  marine  plants.  Life  is  extinguished  at 
the  poles  by  sheer  numbness,  and  these  plants  are 
among  tlie  first  of  living  things  to  resent  that 
effect.  Eocks,  sand,  and  mud  are  here  only  accidents 
of  the  submarine  landscape.  Here  we  no  longer 
find  the  charming  rural  retreats  (if  the  expression 
be  allowable)  of  the  hippocampi,  those  quaint  hybrids 
of  the  creation  :  here  are  none  of  those  republics  of 
stone  built  up  through  age  succeeding  age  by 
armies  of  insect  workmen.  Nature  seems  to  have 
reached  the  end  of  her  resources.  The  beings  con- 
demned to  these  gloomy  solitudes  are  not  the 
creatures  of  a  single  element,  but  pass  their  lives 
alternately  in  the  air  and  in  the  water.  They  are 
like  a  link  between  the  aerial  and  the  submarine 
worlds.  The  sea,  covered  with  thick  masses  of  ice, 
supplies  them  with  but  little  nourishment  in  winter. 
During  this  season,  therefore,  they  hunt  such  land 
animals  as  chance  may  throw  in  their  way;  they 
even   prey  upon   one   another,  and   we   know   how 


INHABITED  REGIONS  OF  THE  OCEAN. 


121 


dangerous  their  neighbourhood  is  to  the  sailor  vn  ho 
is  compelled  to  winter  in  these  inhospitable  regions. 

Thus,  heat  on  the  one  hand,  and  cold  on  the  other, 
arrest  the  extension  of  life  beneath  the  ocean. 

It  is  not  necessary  to  descend  far  below  the  sur- 


face of  the  sea  to  find  the  limits  of  tliat  vital  zone 
which  seems  to  us  at  first  so  immensely  extended. 
At  slight  depths  every  undulation  of  the  surface 
acts  as  a  disturbing  cause,  and  obscures  vision  by 
rapid  alternations  of  light   and    shade.      Soo:i  the 


122  THE  BOTTOM  OF  THE  SEA. 

silence  and  the  darkness  are  not  more  than  momen- 
tarily troubled  by  the  sinking  of  a  cable,  or  the 
1  roken  remains  of  a  wrecked  vessel.  Before  arriving 
at  these  profound  depths  there  are  regions  to  which 
the  light  of  day  but  rarely  and  with  difficulty  pene- 
trates, and  which  yet  are  inhabited  by  legions  of 
living  beings.  From  what  star  unknown  to  us  do 
they  borrow  their  light?  Or  does  their  special 
nature  permit  them  to  substitute  for  sight  a  sense 
more  delicate  still  ?  No  !  these  animals  see  clearly, 
and  one  of  their  functions  is  to  find  light  for  them- 
selves— they  are  phosphorescent. 

Fr^dol  observes :  "  We  are  now  aware  that  the 
infusorise  are  not  the  only  animals  which  cause  the 
phosphorescence  of  the  sea.  This  beautiful  pheno- 
menon is  determined  also  by  the  medusae,  the 
asterias,  the  molluscs,  the  nereids,  and  by  some 
crustaceans  and  fishes.  These  animals  engender  light 
as  the  gymnotus  engenders  electricity.  They  even 
multiply  and  develope  the  effects  of  the  pheno- 
menon. The  light  which  they  produce  rapidly 
changes  from  a  greenish  to  a  reddish  tinge.  At 
certain  moments,  the  darkness  is  lighted  as  by 
radiant  points  running  into  starry  feathers  or  fringes 
of  light.  So  vast  is  the  number  of  these  phos- 
phorescent animals,  that  they  appear  at  a  distance 
like   metallic   masses   heated  to  whiteness,  or  like 


SUBMAllINE    ILLUMINATION.  123 

bouquets  of  lire  formed  of  myriads  of  glittering 
points ;  or,  again,  they  may  be  compared  to  festoons 
of  coloured  lamps  such  as  are  used  in  public  illumi- 
nations— or,  yet  again,  to  burning  meteors,  elongated 
or  globular.  Mingling  and  grouping,  approaching  and 
separating,  ascending  and  descending,  these  wonderful 
wreaths  of  light  describe  a  thousand  capricious 
curves ;  and  if  they  fade  away  or  seem  to  be  extiu- 
giiished,  it  is  only  to  be  rekindled  the  next  moment, 
and  to  pursue  again  the  same  fantastic  course. " 

It  is  in  the  waters  of  the  warmer  latitudes  that 
the  starfishes  display  all  their  brilliance.  The  finest 
illumination  on  the  occasion  of  a  public  feie  can 
scarcely  give  an  idea  of  this  submarine  spectacle. 
Has  the  reader  seen  on  a  fine  summer  evening  the 
flashing  splendour  of  the  myriads  of  fireflies  whicii 
sport  away  tlieir  brief  existence  in  the  valleys  of  Italy 
or  of  Corsica,  and  which  for  their  immense  numbers 
may  be  justly  compared  to  the  sparks  issuing  from  a 
conflagration  ?  Has  he  remarked  in  the  blossoming 
herbage  how  the  pretty  little  glowworm  spreads 
around  it  a  brilliant  red  or  green  light  ?  Imagine, 
then,  glowworms  and  fireflies  mingled  together  in 
all  forms  and  colours,  and  in  such  immense  numbers 
as  to  extend  over  many  hundreds  of  square  leagues ; 
add  to  this  that  every  nook  of  the  vast  region  which 
they  illuminate  has  its  own  proper  light — that  what 


124  THE  BOTTOM  OF  THE  SEA. 

seems  to  us  brown,  lustreless,  and  uniformly  dull  when 
we  observe  it  by  the  light  of  day,  acquires  in  the 
abysses  of  the  Ocean  those  rich  tints  and  phospho- 
rescent gleams  with  which  the  Arab  story-tellers 
liave  glorified  their  dreams  of  fairyland — and  you 
will  have  a  faint  idea  of  the  wonderful  spectacle 
presented  by  the  Ocean  to  the  diver  who  dares  to 
brave  the  innumerable  dangers  of  a  submarine  ex- 
cursion ! 

2.  Migration  of  Marine  Animals — Nests  at  the  Bottom  of  the  Sea — 
Fisheries, 

In  all  ages  man  has  derived  instruction  from  the 
observation  of  nature.  The  sea  above  all  has  sharp- 
ened his  intelligence,  and  therefore  we  are  not  sur- 
prised to  be  told  that  the  nautilus  or  argonaut,  one 
of  the  oldest-known  of  marine  animals,  has  the 
credit  of  having  taught  him  navigation.  The  species 
which  inhabits  the  Mediterranean  (Argonauta  Argo) 
must  in  former  days  have  been  more  widely  diffused 
than  at  present.  It  is  now  found  only  in  the  better 
sheltered  latitudes — the  Archipelago,  the  Adriatic, 
and  the  Straits  of  Messina.  On  a  beautifully  fine  day, 
when  the  air  is  serene  and  the  sea  tranquil,  the 
elegant  shell  of  the  argonaut  may  be  seen  floating 
on  the  water,  which  it  navigates  by  means  of  a 
locomotive  tube,  and  by  spreading  to  the  wind  two 


THE  ARGON AUTA  12t» 

of  its  limbs  furnished  with  fine  silver-coloured 
membranes — the  other  limbs  being  extended,  like 
oars,  on  either  side  of  the  shell.  Gazing  on  this 
elegant  and  living  vessel,  its  delicate  shining  mem- 
branes looking  like  little  wings,  it  is  easy  to  under- 
stand how  Aristotle  and  Pliny  saw  in  the  nautilus 
one  of  the  marvels  of  the  sea,  and  pictured  it  as  a 
representative  in  miniature  of  the  art  of  navigation. 

The  argonaut  is  found  in  many  seas,  but  is  not, 
properly  speaking,  a  traveller.  The  least  billow,  the 
approach  of  the  slightest  peril,  causes  the  timid 
creature  to  draw  in  his  arms,  upon  which,  in  con- 
sequence of  refilling  his  shell  with  water,  he  sinks 
into  the  calm  and  safe  depths  of  the  sea.  His  re. 
treat  is  so  cleverly  managed  that  it  is  extremely 
difficult  to  take  him  captive.  The  officers  of  the 
VaiUant,  desiring  to  obtain  some  of  these  beautiful 
objects,  sent  a  boat's  crew,  during  a  voyage  to  the 
Cape  of  Good  Hope,  to  capture  one  or  more  speci- 
mens ;  but  scarcely  had  the  men  moved  their  hands 
towards  them,  than  the  too  clairvoyant  animals  sud- 
denly tilled  their  shells,  and,  sinking  to  the  bottom, 
left  the  sailors  gazing  at  each  other  in  disappointed 
admiration. 

Attention  has  always  been  attracted  by  the  forms 
of  fishes,  and  from  them,  in  fact,  we  appear  to  have 
borrowed   the   idea   for  the   forms  of  ships.      The 


12G  'J HE  nOirOM  OF  THE  SEA. 

incredible  agility  of  the  dolphin,  which  travels  in  m 
company  so  numerous,  and  gambols  so  joyously  in 
the  track  of  the  sailor,  together  with  the  sudden 
appearance  and  disappearance  of  immense  shoals  of 
fish  at  certain  seasons,  and  the  analogous  migra- 
tion of  birds,  naturally  suggested  that  fish  make  long 
journeys,  and  that  certain  species  accomplish  these 
journeys  periodically.  The  curious  circumstances  of 
these  periodic  expeditions  did  not,  however,  become 
known  until  the  surface  of  the  Ocean  had  been  sub- 
dued by  the  nations  of  the  West ;  until  the  fisheries  of 
Newfoundland,  of  the  coasts  of  Norway,  of  England, 
and  of  Brittany  had  called  the  attention  of  the  learned 
to  tlie  facts,  a  few  instances  of  which  were  alone  known 
to  the  ancients. 

The  tunny  is  among  tlie  number  of  fish  that  were 
known  to  be  travellers  before  tlie  modern  epoch.  It 
is  found  in  the  Mediterranean  moving  in  a  triangular 
phalanx;  one  point  forming  the  advance,  as  if  to 
cleave  the  waves  more  easily,  while  the  base  is  often 
of  great  extent.  It  is  also  abundant  in  the  Grerman 
Ocean,  on  the  coast  of  Guinea,  in  the  region  of  the 
Antilles,  in  the  waters  of  Brazil,  and  in  those  of 
Chili  and  China.  The  warmer  w/iters  are  resorted 
to  by  the  tunny  for  breeding.  Immense  numbers 
pass  the  winter  in  the  eastern  part  of  the  Mediter- 
ranean, where  they  deposit  their  eggs  at  depths  o" 


THli!  TUNNY  AND  HERRING.  127 

abt)Ut  a  Imndred  feet  more  or  less,  avoiding  with 
great  care  the  shoal-water.  Troops  of  them  leave 
the  east  in  the  month  of  May,  and  are  then  to  be 
found  in  abundance  on  the  coasts  of  Sicily  and  of 
Southern  Italy.  In  the  autumn  they  return  to  the 
Tyrrhenian  Sea. 

Pliny  relates  that  the  fleet  of  Alexander  encoun- 
tered such  immense  numbers  of  tunny-fish  that  they 
could  not  make  their  way  through  the  living  mass, 
nor  could  any  noise  or  commotion  they  could  raise 
avail  to  disperse  them.  They  were  compelled  at 
last  to  range  themselves  in  order  of  battle,  as  if  to 
break  through  an  enemy's  line. 

The  dolphin,  the  salmon,  and  tlie  sturgeon  also 
travel  in  companies  of  their  own  species,  but  not 
in  great  numbers.  They  even  mount  the  larger 
rivers,  and  forget,  for  a  time,  the  salt-waters  in 
which  they  had  so  many  enemies  to  encounter.  But 
of  all  fish-travellers,  for  the  distance  traversed  and 
other  points  of  interest,  commend  us  to  the  inhabit- 
ants of  the  colder  parts  of  the  temperate  zone. 

The  herring  occupies  the  first  rank  in  those  classes 
of  animals  of  which  man  has  sufficient  knowledge  to 
convert  them  to  his  profit.  It  abounds  in  the  northern 
seas,  and  it  has  even  been  thought  that  immense 
shoals  of  herrings  live  during  a  great  part  of  the 
year  under  the  polar  ice,  where  they  are  safe  from  the 


128  THE  BOTTOM  OF  THE  SEA. 

attacks  of  tlieir  numerous  enemies.*  However  that 
may  be,  some  naturalists  tliiuk — and,  as  it  appears  to 
us,  with  good  reason — that  duriijg  the  spawning 
season  the  herring  simply  quits  the  level  bottom  of 
the  Ocean  to  deposit  its  eggs  in  the  waters  which 
afford  the  protection  of  rocks  or  of  abrupt  eminences 
against  the  force  of  the  marine  currents. 

Herrings  do  not  obey  simply  the  rule  of  caprice 
in  making  their  migrations.  They  appear  to  select 
the  coasts  towards  which  they  are  travelling:.  As 
all  the  paths  of  the  sea  may  not  be  convenient  for 
thiC  passage  of  a  great  host,  though  small  detach- 
ments may  make  their  w^ay  without  difficulty,  the 
armies  of  herrings  do  not  follow  indifferently  any 
route.  They  traverse  the  regions  where  the  staple 
of  their  nourishment  most  abounds.  Having  visited 
a  coast  they  will  return  there  freely  the  following 
year.  But  suddenly,  without  any  apparent  reason, 
they  may  disap})ear  for  a  time,  or  perhaps  for  ever. 
The  arrival  of  the  mackerel  is  sometimes  the  cause 
of  their  departure.  Being  of  larger  size  than  the 
herring,  as  well  as  better  armed,  the  latter  flies  as  at 
sight  of  an  enemy  too  formidable  to  be  encountered. 


*  The  best  authorities  no  longer  countenance  this  theory.  The 
following  paragraphs,  in  which  tlie  fact  of  the  migration  of  herrings 
is  iinplii  tl,  are  also  open  to  dispute.  The  reader  is  referred  to  the 
Bptcial  works  of  Bertram  and  Mitchell. — Tr. 


Fig.  24.— ilenings  attacked  ly  Tuui.y-liah. 


MIGRATION  OF  HERRINGS  181 

Nearly  all  fishes  are  to  be  more  or  less  dreaded  by 
herrings.  They  fly  like  troops  incessantly  harassed 
by  guerilla  bands  excited  to  the  pursuit.  The  cod, 
the  tunny,  and  the  shark  emulate  each  other  in  the 
destruction  of  these  swarming  multitudes,  whose 
propagation  would  be  too  rapid  if  they  did  not  serve 
as  nutriment  to  tlie  other  inhabitants  of  the  seas. 

During  many  ages  the  coasts  of  Norway  were  the 
favourite  resort  of  herrings.  Thousands  of  vessels 
were  devoted  to  the  fishery.  About  the  year  1600 
they  migrated  towards  the  German  coast,  and  their 
fishery  enriched  the  Hanseatic  cities.  It  is  about  a 
hundred  years  since  immense  shoals  of  them  visited 
St.  George's  Channel.  We  are  equally  ignorant  of 
the  cause  of  their  arrival  and  that  of  their  depar- 
ture. At  the  present  time,  mackerel  are  very 
abundant  on  the  coast  of  Norway.  May  this  fact 
account  for  the  abrupt  departure  of  the  herrings? 
Or  is  it  that  the  herrings  have  not  found,  as  in  St. 
George's  Channel,  a  sufficiency  of  nourishment? 
However  this  may  be,  the  celebrated  Franklin  put 
to  a  profitable  application  the  memory  of  the  herring, 
rind  its  love  for  its  native  place.  Of  two  neighbour- 
ing rivers,  the  one  was  visited  by  a  great  number  of 
these  fish,  whilst  none  appeared  in  the  other.  Frank- 
lin caused  the  nets  covered  with  spawn  to  be  taken 
IVom  the  one  and  placed  in  the  other.     The  herrings 


132  THE  BOTTOM  OF  THE  iS£A. 

did  not  fail,  in  the  following  year,  to  make  their  pil- 
grimage to  the  river  which  had  given  them  birth, 
and  afterwards  both  rivers  were  equally  well  fre- 
quented. 

Tlie  following  facts  will  give  an  idea  of  the  im- 
mense armies  of  herrings  which  invade  our  seas.  The 
single  city  of  Glasgow,  in  Scotland,  exports  annually 
more  than  twenty  thousand  pounds'  worth  in  value. 
In  1773  the  fishery  in  a  single  firth  upon  the  Scottish 
coast  employed  every  night  one  thousand  six  hundred 
and  fifty  boats,  and  the  weight  ol'  the  fish  they  cap- 
tured was  twenty  thousand  tons.  On  one  occasion, 
upon  the  western  coast  of  the  Isle  of  Skye,  their 
number  was  so  great  that  it  was  impossible  to  dispose 
of  them  in  the  usual  way.  Aiter  all  the  smacks  had 
been  filled,  and  the  whole  neighbourhood  was  suffi- 
ciently provided,  the  farmers  used  the  remainder  for 
manure.  For  a  long  time  the  shoal  continued  to 
visit  the  same  coast,  and  appeared  in  the  Sound  of 
Sleat  in  such  immense  numbers,  that  they  quite  filled 
Loch  Hourn  from  one  extremity  to  the  other,  thouirh 
it  is  more  than  half  a  league  in  depth.  The  tide  left  so 
many  behind  it,  that  the  shore  was  covered  to  a  depth 
which  varied  from  three  or  four  inches  to  eighteen 
inches,  and  at  low-water  they  were  visible  as  far  as 
the  eye  could  reach. 

Herring-shoals  are  not  only  very  thick,  but  the  fish 


COD-BANKS  OF  NEWFOUNDLAXD.  133 

are  closely  packed  in  them,  and  in  their  advance 
they  sometimes  drive  all  other  fish  before  them. 
The  shoal  of  which  we  have  just  spoken  had  thus 
driven  before  it  flounders,  skates,  and  other  large 
fish,  which  perished  on  the  shore  among  the  first 
ranks  of  the  herrings.  The  mere  i)ressure  of  the  mass 
forces  those  in  tlie  front  ranks  to  advance,  whatever 
obstacle  presents  itself.  Tliis  fact  is  utilised  in  tlie 
fishery.  Very  long  nets,  to  one  side  of  which  are 
fixed  plummets  of  lead,  and  to  the  otlier  buoys,  are 
let  down  vertically  into  the  sea.  The  meshes  are  large 
enough  to  admit  the  head  of  the  fish,  but  not  to  let 
the  entire  body  pass  through.  If  the  herring  were 
to  try  to  withdraw,  the  openings  of  his  gills  would 
catch  in  the  net  and  make  escape  impossible.  The 
net  is  generally  let  down  at  night,  because  the  her- 
rings are  then  more  abundant. 

The  cod,  that  other  nomad  of  the  sea,  is  found  in 
armies  at  the  meeting  of  the  cold  and  warm  waters 
upon  the  Bank  of  Newfoundland.  An  immense 
quantity  of  small  worms  are  found  in  that  locality,  of 
which  the  cod  makes  his  favourite  food.  Year  by 
year  these  barbarian  hordes  renew  their  invasion — 
every  year  they  are  arrested  in  their  course  by  the 
Gulf  Stream ;  and  after  being  decimated  by  the  fishers, 
their  great  enemies,  the  broken  remainder  of  the 
baud    retire   into  the   polar  seas    to   recruit   their 


134  THE  BOTTOM  OF  THE  SEA. 

strength.  The  fecundity  of  the  cod  is  incredilily 
great.  The  celebrated  microscopist,  Leuwenhoeck, 
counted  in  a  single  individual  as  many  as  nine  millions 
of  eggs.  Their  multiplication  being  so  rapid,  it  is 
easy  to  repair  in  a  single  season  the  losses  of  an 
army. 

Sharks  and  other  great  fishes  destroy  the  cod  by 
thousands ;  man — a  more  terrible  enemy  still,  per- 
haps— makes  a  shambles  of  his  feeding-ground.  What 
a  blessing  it  was  to  these  creatures  when  our  race 
was  confined  to  the  limits  of  the  ancient  world! 
What  a  happy  tranquillity  did  they  not  enjoy,  before 
the  illustrious  Cabots  dared  to  face  the  fogs  and 
frozen  waters  of  Newfoundland  and  Canada ! 

The  cod-fishery  is  by  far  more  dangerous  and  more 
tedious  than  that  of  the  herring.  The  net  cannot  be 
employed  with  the  same  facility,  although  it  is  still 
used  upon  the  coasts  of  Norway.  A  line  is  generally 
substituted  for  it.  To  the  line  is  fixed  a  hook,  with 
a  bait  which  the  cod  is  not  slow  to  seize  hold  of. 
His  weight  renders  the  operation  of  pulling  in  most 
laborious.  To  form  an  idea  of  the  amount  of  work 
done  by  a  fisherman  in  a  single  day,  it  is  enough  to 
state  that  a  strong  man  may  capture  as  many  as  four 
hundred  of  these  fish,  weighing,  on  the  average,  from 
fifteen  to  twenty  pounds  each  ;  some  individuals,  how- 
ever, measurlnr,  nearly  five  feet  in  circumference,  and 


THE  MACKETiEL  Vlb 

from  six  to  seven  feet  in  length,  and  weighing  as  much 
as  eiglity  pounds.  Each  vessel  employed  in  the  fishery 
sends,  on  an  average,  thirty  thousand  cod  to  Europe, 
and  we  know  how  large  is  the  number  of  vessels  en- 
gaged in  the  trade. 

Many  other  fish  furrow  the  vast  extent  of  ocean  on 
every  hand,  swim  in  innumerable  legions  along  the 
coast,  or  hide  themselves  in  the  deeps,  where  the 
calm  promises  them  greater  security.  The  mackerel 
is  of  all  the  most  cosmopolitan.  This  popular  favourite 
visits  every  year  the  coasts  of  Norway  ;  it  abounds  in 
the  markets  of  Germany  and  of  England  during  the 
summer  (the  season  at  which  it  swarms  in  the  North 
Sea  and  the  Baltic) ;  it  is  found  in  equal  plenty  on 
the  coasts  of  Iceland,  of  Ireland,  and  of  Spain  in  the 
Mediterranean.  It  is  fished  by  the  inhabitants  of 
the  Canary  Isles,  in  the  neighbourhood  of  nearly  all 
the  American  islands,  and  even  at  Japan  and  Suri- 
nam. It  disapi^ears  every  year  at  a  certain  time, 
retiring  far  from  the  surface  to  return  again  in  the 
spring.  The  mackerel,  we  may  observe,  in  conclu- 
sion, is  a  great  feeder ;  it  is  so  voracious  that  it  will 
not  hesitate  to  attack  animals  larger  than  itself;  the 
shoals  of  small  fish  which  keep  in  general  near  the 
coast  are,  however,  its  great  resource. 

Small  fish  which  travel  in  shoals  or  immense  herds 
are  next  to  defenceless.     If  the  centre  of  the  lUiiss  is 


IHG  THE  BOTTOM  OF  THE  SEA. 

comparatively  pale  from  the  greater  number  of  th(dr 
enemies,  the  sides  are  exposed  ;  and  the  accumu- 
lation of  such  immense  masses  of  living:  beinf^s  must 
of  course  attract  the  attention  of  rays,  sharks,  and 
other  tigers  of  the  sea.  Some  spe(des  of  small  size, 
such  as  the  anchovy  and  sardine,  are  great  travellers. 
They  dwell  in  the  Atlantic  Ocean  and  the  Mediter- 
ranean Sea.  The  anchovy  also  is  found  in  the  seas 
of  Asia  and  America.  It  passes  from  the  Atlantic 
into  the  Mediterranean  during  the  months  of  May, 
June,  and  July,  and  directs  its  course  towards  the 
xirchipelago  and  the  Syrian  coast.  The  most  consider- 
able fishery  is  in  the  Tuscan  waters,  where  large 
numbers  are  captured  from  April  to  the  end  of  July. 
The  anchovy  is  taken  during  the  night,  when 
there  is  no  moon,  by  means  of  a  boat  called  by  the 
fishermen  a  fastier,  upon  the  deck  of  which  a  fire 
is  made.  Another  boat  carries  a  net  called  a  rissole, 
which  is  more  than  two  hundred  feet  long  by  about 
thirty  feet  in  breadth.  When  the  fastier  is  sur- 
rounded by  a  sufficient  number  of  anchovies,  the 
sailor  in  charge  gives  a  signal  to  his  companions,  who 
throw  the  net  into  the  sea,  and  extend  it  in  such  a 
manner  as  to  surround  the  fish  that  have  been 
attracted  by  the  light.  Suddenly  the  fire  on  the 
fastier  is  extinguished,  the  terrified  anchovies  fly  in  all 
directions,  and  are  of  course  captured  in  the  meshes 


IT  AUNTS  OF  FlSn.  187 

of  tlie  net.  This  method  of  fishing  is  practised  at  a 
distance  of  one  or  two  leagues  from  the  coast.  At  the 
period  of  spawning  a  different  plan  is  adopted.  The 
fish  then  approach  the  shore  to  deposit  their  eggs 
upon  the  shallow  sands,  and  are  caught  in  great 
seines  or  drawnets  in  the  ordinary  way. 

The  sardine  fishery  is  managed  like  that  of  the 
anchovies,  only  the  meshes  of  the  net  are  a  little 
more  open.  The  sardine  is  found  in  its  highest  per- 
fection on  the  coasts  of  Brittany. 

Herrings,  mackerel,  and  col  prefer  to  deposit 
their  spawn  in  rocky  localities  ;  anchovies  love  better 
the  shallow  sandy  bottoms.  Thus  the  character  of 
the  sea-bottom  influences  the  inhabitants  of  the 
deep  in  their  peregrinations.  Some  examples  of  this 
fact  are  generally  known.  The  following  is  one  of 
the  most  remarkable. 

The  Spaniards  for  a  long  time  enjoyed  the  mo- 
nopoly of  the  tunny  trade:  seven  immense  es- 
tablisliments  of  this  fishery  existed  on  the  shores 
neighbouring  the  Straits  of  Gibraltar ;  and  there 
passed  annually  tlirough  the  Pillars  of  Hercules 
more  than  four  hundred  thousand  of  this  fish.  This 
source  of  wealth  was  lost  in  a  single  day,  owing  to 
the  earthquake  whi(;h  overthrew  Lisbon.  The  Span- 
ish coasts  were  rocky,  and  furnished  an  agreeable 
resort  to  the  oceanic  travellers.     On  the  day  of  the 


3  38  THE  BO  TTOM  0  F  THE  SEA . 

earthquake  groat  quantities  of  sand  and  pebbles  were 
torn  from  tne  coasts  of  Africa,  and  thrown  upon 
those  of  Europe.  The  latter  were  thus  converted 
into  shallows  and  sandbanks.  The  tunny-fish, 
having  to  extend  their  journeys  to  the  coasts  of 
Tetuan  and  Sale,  acquired  more  liberty.  It  required 
nets  extravagantly  long  to  capture  them,  and,  in 
fine,  the  fishery  was  transferred  to  the  Sardinian  and 
Italian  coasts. 

It  would  be  very  difficult  to  account  for  the  pre- 
ference shown  by  the  tunny  for  a  rocky  coast.  It 
is  possible,  however,  that  the  facilities  it  affords  for 
shelter  is  the  chief  reason.  Great  and  imposing  as 
the  tunny  looks,  he  is  so  timid  that  he  makes 
scarcely  an  effort  to  escape  from  the  net  after  a  first 
attempt  has  failed,  and  thus  gives  very  little  trouble 
to  the  fishermen. 

The  nets  used  for  the  tunny  fishery  in  the  Medi- 
terranean are  like  enormous  sacks,  which  in  Italy  are 
called  tonndre.  It  is  at  the  commencement  of  April 
that  the  fishermen  begin  to  construct  the  fortress 
into  which  they  expect  the  tunny  to  enter ;  immense 
nets  are  fixed  to  the  bottom,  by  means  of  anchors,  and 
weights  so  heavy  that  the  most  violent  tempest  will 
not  dislodge  them.  The  tunny  loves,  as  we  have 
said,  the  rocky  coasts,  or  passages  between  the  isles. 
It  is  in  such  places  that  the  fishers  establish  their 


THE  TUNNY  FISHERY.  139 

ionnare ;  the  passage  throughout  is  carefully  close  1 
by  nets,  between  which  only  a  small  opening  is  left, 
which  we  may  call  the  exterior  gate  of  the  submarine 
fortalice.  That  gate  which  leads  into  the  first 
apartment,  called  the  halle,  is  made  on  the  side  of 
the  channel  by  which  the  tunny  arrives  every  year. 
When  a  troop  of  these  animals  has  entered  into  the 
Jialle,  the  fishers  close  the  exterior  gate  of  the  ton- 
ndra  ;  they  then  terrify  the  tunnies  by  throwing 
gravel  at  them,  or  by  scarecrows  made  of  sheep- 
skin— or  they  even  pursue  them  until  they  are  induced 
to  pass  through  a  second  gate,  into  the  "ante- 
chamber ;"  this  second  gate  being  then  closed,  the 
first  is  opened  again  to  admit  a  fresh  party  into  the 
halle.  When  a  suflSciently  large  number  of  these 
animals  are  assembled  in  the  antechamber,  similar 
tricks  are  resorted  to  to  drive  them  into  the  chamber 
of  death,  where  the  fishermen  kill  them  with  lances. 
Sometimes  despair  renders  them  furious;  they  fling 
themselves  out  of  the  water,  and  break  their  necks 
or  bruise  their  heads  against  the  rocks  and  boats. 

We  have  reason  to  be  astonished  at  the  facility 
with  which  the  tunny  is  fished,  when  we  recall  to 
mind  its  great  size.  It  is  generally  from  two  to 
three  or  more  feet  long,  but  occasionally  is  consider- 
ably bigger.  It  is  often  found  of  the  size  of  a  man, 
and  luvs  been  taken  from  six-feet-six  to  eight  feet 


140  THE  BOTTOM  OF  THE  SEA. 

long,  upon  the  coast  of  Brazil,  Some  naturalists 
relate  instances  in  which  tunnies  still  longer  have 
been  captured,  and  which  were  otherwise  remarkable 
for  their  unusual  dimensions. 

In  many  other  cases,  and  sometimes  to  capture  a 
prey  less  precious,  man  is  himself  forced  to  descend  to 
the  bottom  of  the  sea.  It  is  thus  that  he  fishes  the 
sponge,  the  pearl,  the  trepang,  and  the  coral.  We 
will  devote  a  special  chapter  to  these  adventurous 
and  barbarous  expeditions.  At  present  we  continue 
our  observations  from  the  shores,  or,  at  least,  we  will 
just  now  explore  such  parts  only  of  the  bottom  as  we 
can   sound  by  means  of  a  boat. 

Here  is  a  quantity  of  spawn  floating  on  the  sur- 
face. This  spawn  is  composed  of  a  number  of  eggs, 
united  by  a  transparent  jelly.  It  serves  as  pasture 
to  fish  of  every  kind ;  but  that  which  is  not  devoured 
will  become  little  fish,  and  be  called  to  higher  desti- 
nies, if  the  sticklebacks,  greediest  of  all  the  small  fry, 
do  not  destroy  it,  or  if  the  swell  of  the  sea  does 
nut  throw  it  upon  the  coast,  where  it  will  corrupt 
and  spread  around  a  phosphorescent  glow. 

At  the  bottom,  the  cod,  the  herring,  the  mackeiel, 
the  tunny,  and  other  fish  have  deposited  their  spa\An 
in  the  crannies  of  the  rocks,  under  the  stones,  in  all 
places  well  defended  against  the  agitation  of  the 
waters.      Notwithstanding    these    precautions,    how 


NESTS  OF  FISH.  141 

many  generations  of  them  are  not  devoured  before 
they  are  hatched,  by  hungry  rovers,  and  often  by 
the  fish  themselves,  who  had  secreted  their  offspring 
with  such  care !  Life  is  preserved  in  the  sea  by  the  in- 
credible fecundity  of  marine  animals,  a  fecundity  of 
which  we  have  now  seen  a  few  examples. 

Some  inhabitants  of  the  seas,  however,  appear  to 
take  the  most  jealous  precautions  to  protect  their  de- 
scendants from  the  attacks  of  a  too  implacable  enemy. 
Some,  like  the  marine  worm,  the  solen,  hide  them- 
selves entirely  in  the  sand ;  others  content  themselves 
with  secreting  their  eggs ;  others,  again,  actually  con- 
struct nests  in  the  algae,  the  leaves  of  which  they 
interlace  for  the  purpose. 

The  stickleback,  in  particular,  so  much  to  be 
dreaded  for  the  fry  of  other  fish,  takes  the  greatest 
care  of  its  own  eggs.  Living  usually  in  the  sub- 
marine forests,  it  is  of  the  most  savage  character.  In 
the  spawning  season,  it  weaves  its  nest  most  ar- 
tistically, and  there  de|X)sits  its  eggs.  Unhappy  is 
the  fish  which  approaches  that  sanctuary :  whatever 
be  its  size,  it  will  have  to  defend  itself  from  the 
furious  attack  of  the  stickleback — it  will  have  to 
bear  stroke  redoubled  upon  stroke  of  its  prickles.  Its 
bites  will  sometimes  rend  the  skin.  M.  Arderon 
relates  that  he  once  preserved  a  stickleback  in  a 
great  jar  of  water,  where  it  devoured  in  five  hours 


142  THE  BOTTOM  OF  THE  JSEA. 

fourteen  small  fry  about  an  inch  long,  and  it  seemed 
to  be  very  comfortable  after  its  sumptuous  repast. 
It  would  not  suffer  any  other  fish  in  the  same  vessel, 
and  attacked  any  that  might  be  put  in,  even  though 
they  were  ten  times  its  own  size.  One  day  M. 
Arderon  put  a  small  fish  in  ;  the  stickleback  imme- 
diately gave  it  chase,  bit  a  morsel  out  of  its  tail,  and  if 
it  had  not  been  taken  from  the  vessel,  it  would  most 
certainly  have  killed  it. 


3.  Terrible  Conflicts  of  Marine  Monsters — Massacre  of  the  Weak 
by  the  Strong. 

Life  is  sustained  by  deatli ;  we  are  constant  wit- 
nesses to  the  truth  of  this  adage.  It  would  seein  as 
if  a  given  quantity  of  life  had  been  conferred  on  the 
globe,  and  that  it  neither  augments  nor  diminishes, 
but  that  it  is  incessantly  transformed  and  renewed — 
in  a  word,  that  all  death  reproduces  an  equivalent 
quantity  of  life.* 

Although  it  is  true  that  man  has  sustained  the 
most  deadly  struggles  against  monsters  since  the 
earliest  ages,  the  memory  of  which  is  perpetuated  in 
legends  and   fables,   he   has  in  later  times  extended 

*  Quantity  cannot  be  predicated  of  life.  M.  Sonrel  occasionally 
philosophises  in  tliis  vein,  and  we  have  generally  allowed  liim  tf) 
have  his  own  way.  If  the  reader  cares  for  another  opinion,  ours  is 
that  this  is  not  the  language  a  i)!iilocopher  ought  to  use. — Tr. 


UTTTJSATION  OF  FISH.  UH 

very  considerably  the  circle  of  his  adventurous  ex- 
peditions. As  the  marvellous  has  given  place  to 
more  exact  ideas  concerning  the  theatre  of  his  ex- 
ploits and  the  nature  of  his  enemies  he  has  felt  his 
audacity  increase  day  by  day.  He  has  driven  his 
keels  through  every  inch  of  the  sea's  surface,  and  he 
has  sought  to  bring  the  powers  of  the  Ocean  under 
the  same  subjection  as  those  of  the  eartli.  He  has 
offered  deadly  combat  to  the  whale,  and  pursued 
him  even  into  the  solitudes  of  the  frozen  regions, 
where  some  sj)ecies  have  taken  refuge  to  escape  his 
blows.  He  derives  from  nearly  all  its  species  a  great 
profit  by  melting  down  their  grease  and  their  liver  to 
extract  an  oil.  The  thick  skin  of  the  greater  num- 
ber of  whales  is  converted  to  numerous  uses ;  the  fins 
of  the  balaena,  the  spermaceti  lodged  in  the  head 
of  the  cachalot,  the  ambergris  which  forms  in  the  in- 
testines of  that  animal  when  he  is  ill,  are  among  the 
articles  of  commerce  furnished  by  the  whale  species. 
It  is  to  the  pursuit  of  these  treasures  that  we  are 
indebted,  in  a  great  degree,  for  our  exact  knowledge 
of  the  habits  of  these  marine  monsters.  Between 
some  of  them  there  prevails  a  sufficiently  good  un- 
derstanding, but  others  appear  to  live  in.  continual 
warfare ;  each  being  ready,  at  an  instant's  notice,  to 
preci[»itate  itself  upon  the  other  wlien  they  meet. 
Such  appears  to   be  thft  case  with  the  bala^na,   or 


144  THE  BOTTOM  OF  THE  HE  A. 

whalebone  whale,  and  the  swordfish,  though  some 
say  the  latter  is  always  the  aggressor,  bailors  report 
that  the  balaena,  whose  vast  mass  imposes  on  nearly 
all  the  inhabitants  of  the  seas,  and  who,  under  his 
thick  cuirass  of  blubber,  may  brave  with  impunity 
their  attacks,  seems  to  be  troubled  in  an  extra- 
ordinary manner  when  he  perceives  the  sworJfish  at 
a  distance.  According  to  the  same  statements,  the 
swordfish  makes  a  rusji  at  the  M'hale,  which  dives  to 
the  bottom  to  avoid  him.  His  enemy,  keeping  close 
in  pursuit,  compels  him  to  remount  to  the  surface. 
The  whale  has  no  other  means  of  defence  but  his 
tail;  with  a  single  blow  he  might  annihilate  his 
enemy,  if  he  could  only  get  at  him,  but  the  swords- 
man is  quite  as  alert  as  his  antagonist  is  strong,  and 
easily  eludes  his  efforts;  he  springs  into  the  air  and 
comes  down  upon  the  whale,  not  to  pierce  him  with  his 
sword,  but  to  give  him  still  more  dangerous  wounds 
with  the  serrated  edge  of  that  terrible  arm.  M.  de 
Tessan  witnessed  an  interesting  combat  of  this  kind 
in  mid-ocean :  the  entry  in  his  diary  is  as  follows  : — 
"Lat.  23°  14'  N.,  Long.  108°  49'  W. ;  16th  Dec, 
1837. — 1  have  had  a  good  view,  although  at  a 
considerable  distance,  of  a  fight  between  a  whale  and 
a  swordfish.  The  latter  leaped  into  the  air,  to  the 
height  of  ten  or  twelve  feet,  made  a  half-turn,  and 
came  down  in  the  water  upon  thy  head  of  ine  whale. 


WUALKS.  147 

His  blows  were  repeated  again  and  again ;  and  tlie 
wliale,  at  eacli  fresh  attack,  struck  the  water  violently 
with  his  tail,  and  often  appeare  I  above  the  surface  to 
blow.  The  combat  lasted  a  long  time,  and  was  always 
confined  to  the  same  spot — which  proves  that  the 
whale  did  not  attempt  to  fly  from  his  enemy.  Sud- 
denly, after  a  moment  of  repose,  tlie  whale  itself 
sprang  from  the  water,  to  a  height  of  about  three 
yards,  and,  coming  down  with  a  crash,  caused  the 
water  to  spring  up  with  great  force.  After  this 
tremendous  effort  the  struggle  appeared  to  cease,  at 
least  I  saw  nothing  more  of  it." 

The  balsena,  or  whalebone  whale,  is  the  least 
voracious  of  the  cetacea.  He  is  much  less  so  than 
the  cachalot  or  spermaceti,  which,  although  of  less 
bulk,  may  nevertheless  be  reckoned  among  the  giants 
of  creation.  The  spermaceti  has  a  large  throat,  and 
is  able  to  swallow  at  a  moutlifiil  a  large  quantity  of 
fish.  Some  curious  statements  are  made,  to  this 
effect,  to  which  it  is  difficult  to  yield  implicit  faith, 
although  they  are  vouched  for  by  naturalists.  *'  A 
spermaceti  whale,  having  beeen  wounded,''  says 
Grantz,  "vomited  a  shark  sixteen  feet  long;  and 
there  were  found  in  his  stomach  the  bones  of  a  fish 
more  than  six  feet  long.  Probably,"  adds  the  same 
author,  "the  fish  that  swallowed  Jonah  was  of  thii* 
Kpecies." 


143  THE  BOTTOM  OF  THE  HhA. 

What  a  monster  this  must  have  been,  which  could 
relieve  the  ocean,  at  a  single  mouthful,  of  one  of  its 
most  dreaded  inhabitants ! 

The  voracity  and  power  of  the  shark  itself  are 
terrible  almost  beyond  credence.  It  is  formidable 
even  to  the  great  cetacea;  it  will  follow,  without 
intermission,  vessels  sailing  in  the  torrid  zone,  and 
devour  whatever  they  let  fall  into  the  sea.  Should 
any  portion  of  the  equipment  or  baggage  fall  over- 
board, it  instantly  becomes  the  prey  of  this  monster. 
Its  jaws,  furnished  with  a  hundred^  and  thirty  strong 
and  pointed  teeth,  are  powerful  enough  to  chop  a 
man  in  two  at  one  blow.  The  only  check  imposed  on 
its  voracity  by  nature  is  due  to  the  position  of  its 
mouth.  Instead  of  being  at  the  extremity  of  its 
body,  it  is  placed  on  the  lower  surface,  at  some 
distance  from  the  snout,  so  that  to  seize  its  prey  the 
shark  is  obliged  to  incline  itself  on  one  side.  While 
it  is  making  this  movement  its  intended  victim  often 
escapes. 

When  it  has  once  tasterl  human  flesh,  the  shark  is 
certain  to  continue  its  visits  to  the  places  where  he 
expects  to  find  it.  For  this  reason  the  pearl-fisheries 
are  the  theatre  of  dreadful  struggles,  in  which  the 
coolness  and  intelligence  tf  man  happily  triumph 
sometimes  over  this  tiger  of  the  seas.  Every  diver, 
when  he   descends,  is   armed   with   a  sharp   knife 


SHARKS. 


149 


When  a  shark  attempts  to  charge  upon  liini,  the 
object  of  the  diver  is  to  stab  him  with  his  knife  in 
the  belly.  The  negroes  of  America  do  not  fear  to 
measure  their  strength  and  skill  against  him.  The 
instant  they  perceive  their  enemy  thoy  dive  to  a  great 


Saildi-  aiiii  .-i  Shui'k. 


depth ;  then,  rising  as  suddenly,  they  stab  the  shaik 
in  the  belly  before  he  has  time  to  take  up  his  offensive 
position. 

But  it  is  not  necessary  to  seek  in  the  annals  of 
negroes  or  Asiatics  for  acts  of  courage  and  of  hand-to- 


150  THE  BOTTOM  OF  THE  SKA. 

hand  struggles  (if  one  may  use  the  expression)  be- 
tween heroic  men  and  their  terrible  adversary.  An 
English  merchant-vessel  having  arrived  at  Bar- 
badoes,  many  of  the  sailors  threw  themselves  into 
the  sea  to  take  a  bath.  An  enormous  shark  advanced 
towards  them ;  every  one  endeavoured  to  reach  the 
ship's  boat  sent  to  their  aid.  At  the  instant  when  he 
was  about  to  escape  from  the  water,  one  of  these 
poor  fellows  was  bitten  in  two  by  the  monster.  The 
friend  of  this  unfortunate  man  was  lashed  into  fury, 
and,  seeing  that  the  shark  was  looking  about  in  the 
bloody  water  for  the  remains  of  his  victim,  the  brave 
young  fellow  sprang  into  the  sea,  resolved  to  perish 
as  his  friend  had  done,  or  make  the  monster  pay  for 
his  audacity  with  his  life.  In  a  moment  the  shark 
made  a  dash  at  the  intrepid  sailor,  and  now  he  was 
close  upon  him.  Already  he  had  turned  himself  over 
on  his  side,  and  opened  his  immense  jaws. 

With  his  left  hand  the  sailor  grippt  d  hold  of  the 
shark  under  his  pectoral  fin,  and  with  his  right  hand, 
in  which  he  held  a  sharp  poniard,  he  struck  him 
blow  redoubled  upon  blow.  It  was  in  vain  the  shark 
endeavoured  to  disembarrass  hi n  self  of  his  enemy  ; 
the  sea  was  dyed  with  his  blood,  and  yet  the  sailor's 
arm  never  seemed  to  tire  of  repeating  the  blows.  The 
men  in  the  boats  belonging  to  the  various  ships 
moored  in  the  road  awaited  with  anguish  the  end  of 


VORACITY  OF  FISH.  Io3 

the  terrible  conflict.  At  length  they  could  breathe 
freely.  Hninan  heroism  and  skill  had  triumphed; 
the  man  was  seen  pushing  the  carcase  of  the  monster 
towards  the  shore,  where  he  tore  out  his  entrails,  and 
took  from  them  the  mangled  remains  of  his  friend. 

Nearly  all  the  other  inhabitants  of  the  sea  are 
voracious;  but  their  small  dimensions,  and  their 
feebleness  relative  to  their  means  of  attack,  render 
them  less  terrible  to  man,  and  mask  their  massacres 
and  depredations  of  all  kinds.  It  needs  tlie  eye  of 
the  naturalist  and  the  sailor  to  observe  those  lesser 
details  of  oceanic  life  which  do  not  affect  us  directly, 
nor  strike  our  imaginations  like  the  more  frightful 
ravages  of  the  great  marine  monsters. 

The  turbot  and  the  sole,  those  deformed  outcasts 
of  society,  as  some  might  think,  are  nevertheless 
your  true  cosmopolites.  They  are  equally  at  home 
in  sandy  and  rocky  places,  but  their  flesh  acquires  a 
preferable  taste  in  the  latter.  They  are  fished  upon 
the  coasts  of  Europe,  at  the  Cape  of  Good  Hope,  in 
the  Indian  Ocean,  and  even  in  the  Chinese  seas. 
Everywhere  they  are  the  prey  of  numerous  enemies, 
yet  let  us  not  be  too  prodigal  of  our  pity  for  them. 
What  they  need  is  strength  alone,  not  voracity.  The 
bait  used  in  their  fisliery  are  morsels  of  hen-ings, 
little  lampreys,  worms,  limpets,  and  mussels.  They 
will  only  eat,  however,  either  living  or  freshly-killed 


154  THE  BOTTOM  OF  THE  SEA. 

flesh ;  they  will  not  bite  at  a  morsel  of  herring  that 
has  been  more  than  twelve  hours  dead.  Look  at  this 
specimen  of  the  delicate  inoffensive  gourmet  !  How, 
with  a  body  so  thin  and  supple,  with  a  mouth  devoid 
of  teeth,  or  any  hard  substance  which  might  supply 
tlieir  place,  could  he  dream  of  becoming  an  assailant  ? 
Nevertheless,  that  animated  leaf  swallows  the  shells 
along  with  their  inhabitants ! 

At  every  step  in  the  sea  we  have  to  note  the  de- 
struction of  the  feeble  by  the  strong,  the  little  by  the 
great.  Let  us  not  forget  that  life  alone  is  capable  of 
sustaining  life ;  it  is  in  general  the  stronger  that  is 
charged  with  the  duty  of  avenging  the  fate  of  the 
feebler.  The  tunny  ruthlessly  destroys  the  herring, 
but  the  pleasures  of  the  chase  are  embittered  by  his 
inevitable  encounter  with  the  shark  ;  and  often  when 
he  is  in  the  very  midst  of  a  delicious  meal  of  herring, 
he  is  himself  victimised  by  the  tyrant  of  the  seas. 

The  entire  life  of  marine  animals  seems  to  be 
passed  in  a  study  or  a  struggle  how  one  shall  eat  the 
other.  The  problem  has  to  be  settled  by  continual 
luses,  attacks  and  precipitous  flights,  battles  and 
deaths,  without  a  spectator  to  compassionate  the 
sorrows  of  the  vanquished.  There  is  no  outcry,  no 
useless  talk  over  these  tragedies.  One  meets  another, 
attacks  him,  devours  him — that  is  all ! 

Tliis     ferocious     cruelty,    this    coldblooded    and 


PUGNACITY  OF  CRAJ18.  155 

implacable  ferocity,  we  do  not  find  in  the  crab.  It 
seems  that  this  gallant  chevalier,  covered  with  a 
thick  cuirass,  has  his  fits  of  anger,  his  joys  after  a 
triumph,  and  is  very  sensible  to  the  dishonour  of 
defeat.  The  most  deadly  combats  will  take  place 
between  crabs  With  their  great  claws  they  seize  on 
the  hind-legs  of  their  adversaries,  and  the  latter  find 
it  no  easy  matter  to  withdraw  their  limbs  safe  and 
sound.  Where  is  the  brigand  that  would  take 
pleasure  in  tearing  his  adversary  limb  from  limb? 
Instances  of  such  cruelty  have  occurred,  but  they  are 
happily  rare.  Procrustes  does  not  often  find  imitators. 
That  which  disgusts  us  is  the  nonchalance  with  which 
crabs  indulge  themselves  in  this  luxury,  often  carrying: 
off  with  them,  as  a  trophy,  a  foot  or  a  leg  of  their 
enemy.  They  are  so  irascible,  that,  if  we  were  to 
put  one  of  his  own  legs  between  a  crab' s  claws,  he 
Would  attack  it  without  perceiving  that  he  was  him- 
self the  aggressor,  and  would  continue  to  pinch  and 
tear  himself  for  a  long  time  after  he  discovered  the  fact. 

It  is  not  always  against  his  own  species  that  the 
crab  directs  his  attacks.     With  his  great  pincers  and 
his  armour-like  shell,  which  render  him  almost  in 
vulnerable,  he  is  the  doughty  enemy  of  all  the  small 
marine  animals. 

But,  as  with  the  knights  of  old,  that  very  armour  is 
sometimes  the  cause  of  danger  to  him.     The  growth 


156  THE  BOTTOM  OF  THE  SEA. 

of  the  shell  by  no  means  keeps  pace  with  the  growth 
of  the  crab.  There  are  times  when  you  will  see  him 
painfully  squeezed  up  in  an  unyielding  garment  too 
small  for  his  body.  Day  after  day  the  bondage 
grows  more  intolerable ;  the  creature's  limbs  are  para- 
lysed, his  whole  life  is  an  agony ;  at  length  the  crisis 
arrives,  and,  with  an  extraordinary  effort,  he  suddenly 
breaks  out  of  his  prison  and  gains  his  liberty.  Many 
die  in  making  this  painful  effort ;  old  crabs  have  had 
the  benefit  of  the  experience  two  or  three  times  re- 
peated. In  the  case  of  the  domestic  crab,  which  inha- 
bits the  craggy  coasts  of  Europe  and  t!ie  West  Indies, 
the  change  takes  place  between  Christmas  and 
Easter.  Until  the  new  shell  acquires  its  destined 
hardness,  the  sole  covering  of  the  liberated  crab  is  a 
skin-like  soddened  parchment ;  in  this  unprotected 
condition  it  retires  into  the  clefts  of  the  rocks,  or 
buries  itself  under  the  sand,  where  it  remains  in  a 
state  of  absolute  immobility.  But  all  these  ruses  are 
of  little  avail ;  its  enemies  pursue  it  witli  an  avidity 
all  the  greater  that  the  crab  is  known  to  be  less 
capable  of  resistance,  and  it  is  with  difficulty  that  it 
escapes  their  vengeance. 

The  lobster  changes  its  shell  like  the  crab.  Some 
days  before  the  period  of  renewal  the  animal  seems 
stupefied ;  he  settles  down  in  a  state  of  torpidity,  and 
the  first  sign  of  returning  activity  is  when  he  throws 


CUAUACTEli  OF  THE  LOBSTEIi.  157 

himself  upon  his  back,  and  battles  with  his  pincers 
one  against  the  other.  Then  a  shudder  runs  through 
his  limbs  and  his  whole  body ;  they  throb  and  dilate, 
the  joints  of  the  armour  open  along  the  belly,  those 
of  the  claws  come  apart — the  moment  of  the  creature's 
deliverance  is  at  hand.  But  when  thus  freed  from 
his  shell,  the  lobster  is  so  feeble  that  he  remains 
altogether  without  motion,  and  in  this  state  becomes 
the  easy  prey  of  cod  and  other  ravenous  fishes.  His 
own  species,  however,  are  in  general  his  most  dan- 
gerous neighbours.  They  have  the  meanness  to 
devour  the  smallest  and  feeblest  of  their  kind,  even 
preferring  them  to  the  little  worms  hidden  in  the 
sand,  or  to  the  spawn  of  fish. 

The  greater  part  of  a  lobster's  life  is  passed  in  a 
retreat  which  he  selects  between  two  rocks.  This 
lurking-place  is  scarcely  larger  than  the  animal 
himself,  and  from  thence  he  springs  with  agility 
upon  his  prey.  The  instant  any  danger  menaces  him 
he  flies  rapidly  towards  his  den,  springing  from  the 
ground  tail-foremost,  and  sometimes  clearing  more 
than  thirty  feet  at  a  single  bound. 

This  armour-plated  brigand,  so  ready  to  pounce 
on  his  defenceless  prey,  is  so  far  from  being  a  hero, 
that  certain  species,  whose  coat-of-mail  is  partly  de- 
fective, are  glad  to  take  refuge  in  the  deserted  shell 
of  a  brother  crustacean.     This  is  the  ca.se  with  tlie 


158  THE  BOTTOM  OF  THE  SEA. 

hermit  or  soldier-crab.  His  armour,  defensive  and 
offensive,  consists  of  two  great  claws,  as  large  ns  a 
man's  thumb,  and  so  powerful  that  they  are  capable 
of  making  very  deep  wounds.  This  ugly  fellow  may 
often  be  seen  on  the  rolled  pebbles  of  a  beach,  drag- 
ging his  old  house  behind  him.  Presently  he  stops 
before  an  empty  crabshell,  he  examines  it  under  all 
its  aspects,  and,  after  \\ithdrawing  his  tail  from  his 
old  abode,  he  tries  to  enter  backwards,  as  his  wont, 
into  the  new  house.  Probably  he  does  not  find  it  to 
his  taste,  in  which  case  he  tucks  himself  into  his 
former  habitation,  and  marches  off  again  in  search  of 
a  more  convenient  apartment.  He  looks  at  one  shell 
after  another,  until  he  finds  an  abode  to  his  liking ; 
he  then  huddles  himself  into  it,  though  it  may  be 
sufficiently  capacious  to  contain  not  only  his  body  but 
his  great  claws.  It  occasionally  happens  that  two  of 
these  animals  select  the  same  shell  for  their  lodging. 
When  this  happens,  they  fight  with  their  claws  till 
the  weaker  is  obliged  to  give  way.  The  victor  then 
takes  possession  of  his  conquest,  and  for  some  time 
marches  boastfully  up  and  down  before  his  discom- 
fited rival. 

Among  the  smallest  of  these  crustaceans,  there  is 
one  (the  Bernhardus,  or  hermit-crab)  which  has  a 
penchant  for  the  shells  of  the  small  molluscs.  It  is 
only  partly  armed,  having  a  helmet  and  a  breast- 


TUE  TORPEDO  AND  GYMNOTUS.  159 

plate,  wliile  the  rest  of  its  body  is  covered  with  a  soft 
skin.  The  hermit  does  not  trouble  itself  to  look  for 
an  empty  shell,  or  to  drive  the  owner  of  a  shell  out 
of  his  home;  lie  wisely  eats  him.  The  CoquiJlauni- 
vaJva — helix-shaped,  liked  our  garden  snail — is  easy 
to  transport.  Having  devoured  the  inhabitant,  and 
comfortably  ensconced  himself  in  one  of  these  shells, 
some  imprudent  neighbour  of  the  supposed  mollusc 
approaches  to  make  a  meal  of  him, — the  crab's  head 
pops  out,  and  the  would-be  eater  is  eaten. 

Let  us  return  to  the  high  seas.  There  we  find 
the  ray,  a  flat  fish,  with  two  different  coloured  sur- 
faces. The  skin  of  some  species  is  so  rough  that  it 
is  employed,  like  that  of  the  sea-cow,  to  polish  ivory 
and  various  woods.  A  powerful  jaw,  in  some  in- 
stances a  tail  set  with  spines,  are  for  the  ray  for- 
midable weapons.  In  fact,  all  these  monsters  are 
apparently  furnished  with  means  of  defence,  and 
breathe  defiance  to  their  victims  even  from  a  dis- 
tance. Sometimes  their  striking  colours,  or  the 
phosphorescent  aureole  which  surrounds  them,  awakes 
the  attention  of  the  feeble,  and  gives  them  time  to 
prepare  for  the  attack. 

In  the  torpedo  and  the  gymnotus  there  is  nothing 
outward  to  suggest  how  terribly  they  are  armed.  The 
one  formed  like  the  raiadae,  the  other  like  an  eel  or 
snake,  they  carry  weapons  more  to  be  dreaded  than 


160  THE  BOTTOM  OF  THE  SEA. 

those  of  any  animals  of  their  species.  Any  fish  that 
approaches  them  is  killed,  as  with  a  stroke  of  light- 
ning, and  devoured  without  a  struggle.  Touch 
them,  and  a  shock  is  given  like  that  of  an  electric 
charge ;  yet  certain  authors  assure  us  that  the  negroes 
handle  the  torpedo  without  danger. 

The  electrical  power  of  the  gymnotus  was  unknown 
in  Europe  until  1671,  when  the  astronomer  Eicher, 
who  was  sent  on  a  mission  to  Cayenne  by  the  French 
Academy  of  Sciences,  observed  and  made  known  the 
remarkable  power  of  this  fish.  "  I  was  much  as- 
tonished," says  Richer,  "  to  see  a  fish  resembling  an 
eel,  some  three  or  four  feet  in  length,  deprive  of  all 
motion  for  a  quarter  of  an  hour  the  arm  and  shoulder 
of  one  who  touched  it  with  his  finger  or  with  a  stick. 
I  was  not  only  an  eyewitness  of  this  effect,  but  1 
have  myself  felt  it  on  touching  one  of  these  fishes, 
still  living,  though  wounded  by  the  hook  with  which 
the  Indians  had  drawn  it  from  the  water." 

The  savans  of  Paris  were  at  that  time  a  sceptical 
people.  Richer 's  account  made  so  little  impression 
on  them,  that  for  seventy  years  no  naturalist  troubled 
himself  to  inquire  into  it.  This  indifference  lasted  to 
the  time  of  Condamine,  who  spoke,  in  his  "  Voyages 
en  Amerique,'^  of  a  fish  which  produced  the  effects 
described  by  Richer.  The  phenomenon  now  excited 
attention.     Dr.  Ingram  published  some  views  about 


ANIMATED  FORESTS.  IGl 

it  in  1750,  and  attributed  the  effects  to  electricity. 
The  Dutch  pliysiciau  and  philosopher,  Gravesende, 
recognised  the  galvanic  nature  of  tlie  shocks  given 
by  this  animal.  "  The  effect  produced  by  this 
fish,"  he  wrote  in  1755,  "  is  the  same  as  that 
caused  by  the  Leydeu  jar,  only  .with  this  difference, 
that  no  spark  is  observed,  however  strong  the  shock 
may  be ;  for  if  the  fish  is  a  large  one,  those  who 
touch  it  are  struck  down,  and  feel  the  shock  through 
their  whole  body." 

The  gymnotus  does  not  seem  to  make  any  use  of 
his  weapon  except  in  self-defence.  He  feeds  on 
small  fishes  and  worms,  of  which  great  numbers  are 
found  in  the  waters  of  South  America  and  the  Indian 
seas.  The  torpedo  is  more  cosmopolitan  ;  it  is  no- 
toriously frequent  in  the  seas  of  Europe.  These  two 
monsters,  depositories  of  thunder,  appear  to  share 
between  them  the  universe  of  waters.  Like  the  ray, 
the  turbot,  and  the  sole,  the  torpedo  prefers  for  his 
portion  the  sandy  flats  and  shallows ;  the  gymnotus 
hides  among  the  rocks,  in  clear  waters,  and  in  the 
neighboui'hood  of  rivers,  which  he  often  ascends. 


4.  Animated  Forests — Animal  Stones. 

The  bottom  of  the  sea  is  an  enchanted  country  : 
the  animals,  its  inhabhants,  are  self-luminous;  they 

M 


16'2  THE  BOTTOM  OF  THE  SEA, 

thunder  upon  their  enemies  from  a  distance;  tliey 
harden  themselves  into  stone. 

We  read  that  Daplme  was  transformed  into  a 
laurel.  The  narrators  of  this  fable  have  not  depicted 
for  us  the  sufferings  of  that  unfortunate  maiden,  her 
languor,  the  growing  numbness  of  her  limbs,  her  feet 
dried  up  and  spreading  into  long  roots,  her  arms 
shaping  into  branches  covered  with  a  polished 
bark.  But  this  dream  is  realised  in  the  Ocean  every 
moment.  There  is  no  region  with  a  favourable 
climate  and  an  agreeable  site,  where  animals  are  not 
found  living  in  colonies,  and  working,  by  their  petri- 
faction, at  the  construction  of  rocks  and  reefs  of  an 
immense  extent. 

Heat  favours  their  development.  No  part  of  the 
world  presents  them  in  the  same  marvellous  variety 
as  the  Great  Ocean  and  the  Indian  seas  :  "  If  we  direct 
our  gaze  into  the  liquid  crystal  of  the  Indian  Ocean, 
we  shall  there  see  realised  the  most  wonderful  dreams 
and  fairy-tales  of  our  childhood.  Fantastic  bushes 
bearing  living  flowers,  the  massive  structure  of  the 
meandrina  and  astrea  contrasting  with  the  branchy 
tufts  of  the  explanaria,  which  blossom  in  the  form  of 
cui)s,  with  the  madiiporidae,  of  elegant  structure  and 
ever-varvino:  ramifications.  Evervvvhere  throuo^hout 
this  region  the  eye  is  charmed  with  the  brilliancy  of 
colour :  delicate  shades  of  sea-green  alternating  with 


COLOUR  OF  MARINE  VEGETATION.  163 

browns  and  yellows,  rich  purple  tints  passing  from 
the  most  vivid  red  to  the  deepest  blue ;  nullipores, 
yellow  or  pink,  delicately  touched  as  the  peach, 
covering  decaying  plants  with  a  fresh  development 
of  life,  and  themselves  enveloped  with  a  black  tissue 
of  retipores  resembling  the  most  delicate  carvings 
in  ivory.  Near  by  wave  the  yellow  and  lilac;  fans  of 
the  gorgona,  worked  liked  jewelry  in  filigree. 
Strewn  over  the  sandy  bottom  are  thousands  of 
sea-stars  and  sea-urchins  of  the  most  curious  forms  and 
varied  colours.  The  ilustra,  the  eschara  attached 
to  bran(;hes  of  coral-like  mosses  and  lichens,  and 
the  patellidae  striped  with  yellow  and  purple,  look 
like  great  cochineal  insects  on  the  ground.  Then 
the  sea-anemones,  looking  like  immense  cactus-flowers, 
brilliant  with  the  most  glaring  colours,  adorn  the 
clefts  of  the  rocks  with  their  waving  crowns,  or 
spread  out  their  blooms,  till  the  sea-bottom  resemble* 
a  border  of  many-coloured  ranunculuses.  Around 
the  coral-bushes  play  the  hummingbirds  of  the  ocean 
— brilliant  little  fishes,  now  sparkling  with  metallic 
red  or  blue,  now  with  a  golden  green,  or  with  the  soft 
hue  of  silver.  All  this  marvellous  manifestation  of 
life  is  displayed  in  the  midst  of  the  most  rapid  alter- 
nations of  light  and  shade,  changing  with  every 
breath,  with  every  undulation  that  ripples  the  sur- 
face of  the  sea.    When  daylight  declines,  the  shadows 


164  THE  BOTTOM  OF  THE  SEA. 

of  night  spread  in  the  deep  waters,  the  exquisite  garden 
which  they  cover  is  lighted  up  with  new  splendours. 
The  medusae  and  the  microscopic  crustaceans  shine 
in  the  darkness  like  fairy-stars.  The  pennatula,  which 
during  the  day  is  of  a  reddish  cinnabar  colour,  floats 
in  a  phosphorescent  h'ght ;  every  corner  of  the  sea- 
bottom  sends  out  its  ray  of  colour ;  objects  that  look 
brown  and  dull  in  the  universal  radiation  of  daylight, 
now  shine  with  the  most  charming  green,  yellow,  and 
red  light ;  and  to  complete  the  marvels  of  this  en- 
chanted night-scene,  the  large  silver  disc  of  the  moon 
of  the  sea  {Orthagoriscus  mola,  commonly  called  the 
moon-fish),  moves  softly  through  the  whirling  vortices 
of  little  stars.  The  most  luxuriant  vegetation  of  the 
tropics  fails  to  develope  so  much  wealth  of  form,  and 
lags  far  behind  the  magnificent  gardens  of  the  ocean, 
composed  almost  entirely  of  animals,  for  variety  and 
brilliance  of  colour.  That  marine  fauna  is  not  less 
remarkable  for  its  extraordinary  development  than 
the  abundant  vegetation  of  the  bed  of  the  sea  in  the 
temperate  zones.  All  that  is  beautiful,  marvellous, 
or  extraordinary  in  the  great  classes  offish,  of  echino- 
dermata,  of  medusae,  of  polypi,  and  of  shell-covered 
molluscs  bred  in  the  warm  and  limpid  waters  of  the 
tropical  ocean,  repose  there  on  the  white  sands,  at- 
tach themselves  to  the  rough  rocks,  or  (should  the 
place   they  covet  be  already  occui)ied)  fasten   like 


SPONGES.  165 


parasites  on  other  existences  as  wonderful  as  them- 
selves, or  float  on  the  surface  and  in  the  depths  in  the 
midst  of  a  vegetation  relatively  rare."* 


5.  Sponges. 

For  a  long  time  the  zoophytes  were  taken  for  in- 
durated marine  plants.  Their  animal  nature,  and 
their  likeness  to  animals  under  forms  and  aspects  so 
grotesquely  various,  were  not  thoroughly  recognised 
until  our  own  times ;  the  name  they  still  retain  re- 
calls their  apparent  analogy  to  vegetables. 

Tlie  characters  of  animality  which  they  present 
endure  but  for  an  insignificant  period  of  their  exist- 
ence. At  first  they  move  freely  in  the  water,  some 
solid  body  arrests  them  in  their  course,  the  young 
animal  whose  body  is  sometimes — in  the  sponges,  for 
example — surrounded  with  vibratile  cilise,  attaches 
itself  to  the  obstruction,  where  it  soon  loses  all  power 
of  movement,  and  commences  a  series  of  strange  meta- 
morphoses. The  body,  at  first  gelatinous,  breaks 
into  holes,  which  change  by  extension  into  winding 
canals,  traversing  the  mass  in  all  directions.  In 
these  winding  channels  the  water  circulates,  and 
brnigs  to  the  animal   whatever   substance   may  be 

*  Schleitlen,  La  Plunte  el  sa  Vie. 


166  THE  BOTTOM  OF  THE  SEA. 

necessary  to  its  development.  The  creature  has  lost 
its  mobility,  and  become  to  all  appearance  an  inert 
mass.  It  resembles  a  most  irregular  and  ill-formed 
vegetable ;  the  holes  begin  to  bristle  with  horny  fila- 
ments entangled  one  in  the  other,  and  constituting  a 
kind  of  solid  carpentry.  By-and-by  other  siliceous 
or  calcareous  filaments  mingle  with  the  first,  and  fill 
up  the  cavities  which  had  been  left  among  them. 
The  forms  of  these  are  most  varied  according  to  the 
species  to  which  they  belong,  and  often  spiculse  very 
different  in  their  aspect  are  combined  in  the  same 
individual.  They  are  generally  so  small  that  their 
nature  is  only  discovered  by  means  of  the  microscope. 
With  its  aid  some  are  seen  to  be  shaped  like  har- 
poons, some  like  stakes  with  pointed  ends,  some  like 
stars  or  crystal  knots  of  the  most  curious  forms. 

The  various  species  of  sponge  are  distinguished  by 
their  tissue  being  more  or  less  close,  more  or  less 
crooked .  Sometimes  their  mass  is  surrounded  in  nearly 
every  part  with  a  siliceous  or  calcareous  envelope. 
The  coasts  of  Europe  furnish  some  sponges  of  this  kind, 
but  the  most  remarkable  come  from  the  sea  of  the 
Antilles  and  from  that  of  Japan.  Sometimes  the 
siliceous  spiculse  fill  the  tissues  so  completely  that  the 
sponge  serves  as  a  polishing  material.  The  use,  how- 
ever, to  which  the  sponge  is  generally  destined  is 
suggested  by  the  facility   with   which  it  takes   up 


s 
o 


STRUCTURE  OF  SPONGES.  169 

water.  Most  of  the  species  are  unfit  for  that  pur- 
pose ;  they  are  very  numerous,  and  appear  to  inhabit 
indifferently  every  sea,  being  more  abundant,  how- 
ever, near  the  equator. 

The  Red  Sea,  the  coasts  of  Syria,  the  seas  of 
America,  the  Middle  Atlantic,  and  the  Southern  Seas, 
are  rich  in  sponges  capable  of  serving  for  domestic 
purposes. 

Sponges  are  torn  from  the  rocks  to  which  tliey  are 
attached  by  divers,  who  pursue  their  trade  more  par- 
ticularly in  the  seas  of  Asia.  Should  we  not  feel 
astonished  by  the  low  price  at  which  they  can  be 
sold,  when  we  reflect  that  every  sponge  collected  in 
the  submarine  forest  has  been  gathered  at  the  risk  ot 
death  to  one  of  these  unfortunate  men,  to  whom  ]i  c 
is  nothing  but  one  long  agony  ? 

At  certain  periods  of  the  year  certain  ovoid  or 
spherical  corpuscles  are  developed  in  the  spongy 
mass,  and  thence  pass  into  the  channels  with  which 
the  sponge  is  pierced.  Carried  out  into  tlie  sea  by 
the  currents  of  water  which  circulate  in  these  chan- 
nels, they  propagate  the  sponge  in  the  manner  de- 
sciibed  above. 

When  the  spongy  mass,  for  any  reason  whatever, 
decays  oi-  breaks  up,  the  spiculae  are  scattered  upon 
the  bottom.  In  some  seas,  such  as  the  Indian  Ocean, 
the  sea  of  coral,  the  specimens  of  the  bottom,  taken 


170  THE  BOTTOM  OF  THB  SEA. 

from  the  depth  of  about  four  miles,  are  principally 
formed  of  these  spicnlse;  they  accumulate  in  thick 
and  far-extended  beds,  the  importance  of  which  in 
course  of  time,  relative  to  the  surface-form  of  the 
globe,  must  be  very  considerable. 


6.  Polypi — Their  general  structure — Reproduction  of  Polypi — 
Vegetative  life  of  Polypi — The  Polypier — Two  great  classes 
of  Polypi  distinguished  by  the  form  of  the  Polypier — The 
Tubipora  musica. 

Most  of  the  polypi  live  in  colonies,  and  find  a  point 
of  support  on  the  rocks.  We  say  live,  but  more 
strictly  speaking  they  vegetate,  their  movements 
being  extremely  limited.  Their  bodies  become  en- 
crusted with  calcareous  matter,  and  life  gradually 
withdraws  from  the  petrifying  animal.  Eggs  aban- 
doned to  the  sea  at  various  periods  of  the  year,  or 
buds  developed  on  the  polypus,  are  two  methods 
equally  common  by  which  they  are  propagated. 

The  body  of  the  polypus  is  soft ;  its  form  is  that 
of  a  hollow  cylinder;  at  one  of  its  extremities  an 
opening  serves  for  the  introduction  of  aliment  into 
the  body  of  the  animal,  and  for  the  expulsion  of 
matters  which  have  not  served  for  its  nutrition.  This 
single  opening  of  the  body  is  surrounded  with  fleshy 
appendices  or  tentacles,  more  or  less  numerous  ;  the 
digestive  apparatus,  however,  is  not  always  marked 


STRUCTURE  OF  POLYPI.  171 

by  this  simplicity  of  structure.  It  is  often  formed  of 
a  double  pocket,  the  one  completely  enveloping  the 
other.  The  animal  in  this  case  might  be  well 
enough  described  as  a  sack,  closed  at  one  of  its  ex- 
tremities, and  with  its  suj^erior  or  opened  part  folded 
back  upon  the  bottom. 

The  tentaculae  are  always  hollow,  and  all  the 
cavities  communicate  one  with  another.  Leaf-like 
formations,  or  foldings  of  the  envelope  of  the  body 
close  the  internal  cavity ;  the  walls  of  that  cavity 
reunite  at  the  base  of  the  animal.  They  contract  or 
they  dilate  at  its  pleasure,  in  order  to  give  free  pas- 
sage to  the  aliment  prepared  for  nourishment  in 
that  first  chamber.  Matters  unfit  for  nutrition  are  at 
the  same  time  ejected,  by  the  only  door  which  lias 
given  them  entrance.  Between  the  wall  of  this 
stomach,  and  the  exterior  envelope  of  the  animal's 
body,  a  sort  of  double  bottom,  imperfectly  partitioned 
off,  collects  the  aliments  that  have  been  suitably 
prepared,  and  it  is  there  that  the  eggs  of  the  animal 
are  lodged. 

The  spaces  left  between  the  foldings  of  the  skin  in 
that  second  pouch  are  prolonged  into  the  tentaculae, 
which  the  animal  can  withdraw  into  itself  at  will, 
or  spread  out  like  the  blossom  of  a  flower.  Fig.  29 
shows  the  polypus  in  its  various  degrees  of  expansion. 
The  entire  polypus  is  enveloped  in  a  great  number  of 


172 


THE  BOTTOM  OF  THE  SEA. 


species,  with  a  tough  sheath  from  which  it  projects 
itself  at  will.  Fig.  30  represents  a  number  of  such 
polypi  indrawn — that  is  to  say,  with  the  body  of  the 
polypus  retracted  and  hidden  under  the  protecting 
envelope  which  surrounds  its  base. 


jitj^ 


Fig.  29. — Coral  with  Polypi  more  or  less  expanded. 

The  polypi,  whose  digestive  apparatus  is  formed  of 
a  single  pouch,  are  called  hydras  or  sertularias ;  those 
whose  digestive  apparatus  is  formed  of  a  double 
pouch,  are  corallines,  or  polypi  proper. 

The  inferior  extremity  of  the  polypus  is  the  pro- 
longation of  that  envelope,  but  more  hardened,  in 


THE  rOLYPIER. 


173 


which,  as  we  have  seen,  the  animal  lias  power  to 
shut  itself  up.  It  is  the  point  of  adherence  to  the 
foreign  body,  to  which  the  polypus  fixes  itself. 

Polypi  reproduce  themselves  in 
two  different  ways — by  eggs  and  by 
buds.  The  egg^,  or  larvae,  are 
lodged  on  the  walls  of  the  only 
cavity  which  encloses  the  body  of 
the  animal.  At  certain  periods  of 
the  year,  they  leave  the  body  and 
float  in  the  water,  as  we  have  seen 
is  the  case  with  the  sponges  also, 
until  they  meet  with  a  place  upon 
which  they  can  root  themselves. 

We  have  already  observed  that     ''''g-  30.— liranch   of 

Coral    with    Polvpi 

the  sponge,  durmg  a  greater  part  in.iiawu. 
of  its  existence,  lives  a  vegetative 
life.  So,  when  a  polypus  is  once  fixed  upon  a  solid 
body,  its  base  extends.  If  other  animals  of  the  same 
species  join  it  to  form  a  colony,  or  if  it  produce  buds, 
the  mass  gradually  increases.  Each  polypus  secretes 
a  matter  which,  on  hardening,  becomes  horny  or 
stony,  and  constitutes  the  polypier,  or  polypus  tree. 
The  nature  and  form  whicli  the  polypier  gives  to  the 
colony  serves  to  characterise  the  different  kinds  of 
animals  of  this  class. 

An    inspocti(.n    of    tlu;    polypier    constructed     by 


174  THE  BOTTOM  OF  THE  SEA. 

polypi,  suggests  their  division  into  two  great  classes, 
a  division  which  has  been  already  indicated  by  the 
essential  difference  we  have  pointed  out  in  the 
digestive  apparatus  of  the  different  species.  The 
hydras  grow  from  the  exterior — that  is  to  say,  they 
surround  themselves  with  a  horny  or  stony  envelope, 
whilst  they  have  no  interior  calcareous  basis  or 
polypier.  The  corallines  present  a  character  alto- 
gether the  opposite.  They  have  an  internal  polypier — 
that  is  to  say,  the  hardest  parts  of  the  polypus  tree 
are  in  the  interior,  and  the  living  bed  in  the  midst  of 
which  are  the  polypi  is  superficial. 

One  particular  kind  of  polypus,  originally  from  the 
Indian  Ocean,  produces  a  very  remarkable  polypier. 
It  is  formed  of  tubes  in  regular  juxtaposition  with 
each  other,  and  joined  by  transverse  partitions  run- 
ing  from  one  to  the  other  (fig.  31).  It  is  for  this 
reason  called  the  TuUpora  musica,  or  organ-pipe 
coral.  The  tubes  are  placed  next  to  each  other,  like 
those  of  a  mouth-organ.  In  the  engraving  it  is  re- 
presented half  the  natural  size. 

The  organ-pipe  coral  is  of  a  beautiful  red  colour. 
The  first  naturalist  who  observed  it  in  the  Indian 
Ocean  took  it  for  a  colony  of  great  marine  worms,  and 
it  is  only  in  recent  times  that  its  true  nature  has  been 
fully  understood. 

This  polypus  is  not  an  ordinary  hydra,  not  with- 


ORQAN-riFE  COliAL.  175 

6tandiug  the  tubular  form  assumed  by  the  hardened 
envelopes.  The  polypi  in  the  tubipora  are,  in  fact, 
completely  independent  of  one  another.  When 
fresh  inhabitants  are  added  to  the  colony,  they  grow 
by  placing  themselves  parallel  to  their  predecessors, 
to  whom  they  are  attached  by  transverse  partitions. 


Fig.  31. — Organ-pipe  Conil. 

Each  polypus  lives  and  grows  in  its  own  tube,  and 
holds  no  relations  with  the  others,  exce})t  that  of  good 
neighbourhood,  w  hen  it  leaves  its  abode  to  spread  its 
snares  for  the  little  marine  animals.  It  is  not  so 
with  the  true  hydras.  In  them  the  hardened  enve- 
lope resembles  a  continuous  canal,  uniting  all  the 
polypi  one  with  another.  At  whatever  point  of  the 
common  trunk  a  bud  is  produced,  the  calcareous 
matter  envelopes  it,  and  establishes  its  immediate 
relationship  with  the  rest  of  the  colony. 


176  THE  BOTTOM  OF  THE  SEA. 


7.  Hydra,  type  of  the  Hydrozoa  or  Hydra  Polyps— Extraordinary 
properties  of  the  Hydra  discovered  by  Trembley— Marine 
Hydrozoa. 

The  hydrozoa  owe  their  name  to  a  special  type, 
the  hydra,  which  inhabits  fresh  waters.  The  cele- 
brated naturalist  Trembley,  tutor  to  the  sons  of 
Count  Bentinck  in  Holland,  was  the  first  to  re- 
cognise their  nature,  in  1740.  The  remarkable  pro- 
perties which  he  discovered  among  these  little  beings 
struck  the  learned  of  the  eighteenth  century  with 
astonishment.  The  flesh-eating  habits  and  the  spon- 
taneous movements  which  he  had  remarked  among 
the  hydrae  led  him  to  believe  they  were  animals,  while 
their  appearance  resembled  that  of  aquatic  plants. 

Trembley  made  the  following  decisive  experi- 
ment. Plants  have  the  property  of  reproducing 
themselves  by  cuttings — that  is  to  say,  a  branch  of 
the  plant  being  cut  off,  and  planted  under  suitable 
conditions,  roots  develope  themselves  at  the  cut  ex- 
tremity, and  the  branch  becomes  a  plant  similar  to 
its  parent.  As  no  known  animals  possessed  thL<» 
singular  faculty,  it  was  to  be  presumed  that  the 
hydra  would  not  reproduce  itself  by  cuttings.  What 
then  was  the  astonishment  of  Trembley  when  he 
observed,  some  days  alter  the  mutilation  of  a  polyp, 
each   morsel    transformed   into   a    complete    body. 


THE  HYDROZOA.  177 

having  the  same  characters  as  the  creature  of  which 
it  had  hitely  formed  a  part ! 

Evidently  sc-ieDce  had  become  enriched  by  the 
discovery  of  a  new  fact.  Her  classification  had 
proved  defective,  inasmuch  as  an  attribute  con- 
sidered as  peculiar  to  plants  had  been  proved  by 
this  experiment  to  belong  to  creatures  of  which 
the  animal  nature  was  incontestable.  Henue,  not- 
withstanding the  difficulty  of  communication  among 
the  learned  in  those  days  compared  witli  the  present 
time,  this  new  experience  was  speedily  rumoured 
throughout  Europe.  Every  naturalist  repeated  the 
experiment  for  himself:  at  first,  upon  polypi  which 
Trembley  sent  in  his  letters,  after  having  had  them 
properly  dried ;  afterwards  upon  specimens  which 
they  found  for  themselves  in  stagnant  waters. 
Reaumur  was  one  of  the  first.  "I  declare,"  said  he, 
*'  when  I  saw  for  the  first  time  two  polyps  gradually 
form  themselves  from  one  that  I  had  cut  into  two 
pieces,  I  could  hardly  believe  my  eyes ;  and  the  truth 
is,  I  am  not  yet  accustomed  to  the  belief,  although 
I  have  repeated  the  experiment  a  hundred  times 
over."  Soon  afterwards,  Reaumur  began  to  observe 
the  same  phenomenon  in  various  species  of  worms, 
and  that  which  had  seemed  incredible  was  soon 
recognised  as  being  but  another  of  the  common  phe- 
nomena of  nature. 


178  THE  BOTTOM  OF  THE  SEA. 

This  is  but  one  example  of  the  fate  common  to 
great  discoveries.  At  first,  people  are  astonished  by 
them,  and  receive  them  incredulously  ;  aft(irwards,  as 
facts  accumulate,  it  seems  as  if  each  experimenter  had 
either  made  the  discovery  for  himself,  or  very  nearly 
approached  it.  If  the  reader  has  followed,  even  in  a 
general  sort  of  way,  the  scientific  movement,  he  will 
be  able  to  recall  in  illustration  of  this  fact  the  new 
ideas  introduced  into  meteorology  by  the  learned 
physician,  M.  Marie  Davy ;  how  doubtfully  his  first 
communications  upon  the  general  cause  of  storms 
was  received,  how  people  hesitated  in  the  very  pre- 
sence of  the  facts  by  which  the  exactness  of  his  obser- 
vations was  verified,  and  how  the  merit  due  to  the 
first  observer  has  finally  been  acknowledged. 

Let  us  return  to  Trembley's  hydra.  Its  body  is 
soft,  and  consists  of  one  long  pouch  with  a  single 
opening.  The  pouch  is  surrounded  with  tentacles, 
which  in  the  species  we  are  describing  are  six  in 
number.  On  the  walls  of  the  membranous  sac  which 
constitutes  the  animal,  the  buds  or  eggs  develope 
themselves.  The  latter,  having  arrived  at  a  certain 
size,  leave  their  first  home  and  float  freely  in  the 
water.  The  buds  can  either  separate  themselves  from 
the  mother  hydra,  or  remain  fixed  to  her  ;  in  the  latter 
case  the  same  foot  or  stalk  bears  two  hydras,  the 
one  of  which  is,  so  to  speak,  grafted  upon  the  other. 


TREMBLEY*S  HYDRA.  179 

Hydras  are  found  in  grassy  waters,  lakes,  pools, 
and  canals.  The  best  mean  cf  procuring  them  is 
to  take  haphazard,  from  the  water  supposed  to 
contain  them,  any  aquatic  plants,  leaves  of  trees 
that  have  fallen  into  the  water,  or  bits  of  wood 
which  have  accumulated  there,  and  to  these  the 
hydras  will  be  found  attached.  They  transport 
themselves  from  one  point  to  another  by  swimming 
or  crawling. 

Trembley  has  made  a  special  study  of  three  species 
of  hydra.  He  has  named  them  the  long-armed  poly- 
pus, green  pohjpuSy  and  hrmvn  or  grey  polypus  (Hydra 
Grisea).  Their  bodies,  which  are  very  contractile, 
are  variously  formed.  The  tentaculaB  are  often 
immoveable.  The  ordinary  species,  including  their 
arms,  may  reach  five-eighths  of  an  inch  in  length, 
but  other  species  attain  larger  dimensions. 

Ancient  writers  mention,  under  th(j  name  of  hydra, 
a  mythologic  animal  with  seven  heads,  each  of  which 
was  reproduced  as  fast  as  it  was  cut  off.  Trembley 's 
hydra,  more  accomplished  than  this  fabulous  animal, 
formed  two  perfect  creatures  when  divided.  Nor 
is  this  all.  What  does  the  reader,  when  made 
acquainted  with  the  fact  for  the  first  time,  think  of 
an  animal  able  to  turn  itself  inside-out  like  a  glove 
without  ceasing  to  live  ?  Trembley  tells  us  that  his 
hydra  undergoes  this  operation  without  being  in  the 


J 80  THE  BOTTOM  OF  THE  SEA. 

least  degree  incommoded.  *'I  have  seen,"  he  says, 
in  his  fourth  memoir,  "a  i)olypus  turned  inside-out, 
which  has  eaten  a  little  worm  two  days  after  the 
operation.  Others  have  not  recovered  their  appetite 
so  quickly;  they  have  been  four  or  five  days,  more  o" 
less,  without  wanting  to  eat.  Alter  that  time  they 
ate  as  well  as  other  polyps  which  had  retained  their 
proper  insides.  I  have  kept  a  polyp  that  had  been 
turned  inside-out  more  than  two  years.  His  progeny 
had  become  very  numerous.  Once,  when  I  had  suc- 
cessfully turned  a  few  polyps,  I  was  impressed  to 
repeat  the  experiment  in  'the  presence  of  good  ob- 
servers, that  I  might  be  able  to  cite  other  evidence 
than  my  own  in  proof  of  this  strange  fact.  I  succeeded 
so  well  that  others  attempted  to  follow  my  example. 
Monsieur  Allamand,  whom  I  begged  to  try,  suc- 
ceeded as  well  as  myself.  He  has  turned  many 
polyps,  and  some  that  he  experimented  upon  have 
remained  inside-out  and  continued  to  live.  He  has 
even  done  more  than  this :  he  has  turned  polypi  again 
which  had  been  turned  some  time  before,  and  this 
although  they  had  eaten  after  the  first  experiment. 
He  even  found  that  they  ate  as  well  after  the  second 
operation.  Finally,  he  turned  some  a  third  time,  but 
they  died  alter  a  few  days,  without  having  recovered 
their  appetites.  Whether  their  decease  was  owiui^ 
to  the  operation  or  not  cannot  very  well  be  decided." 


^h'A-W'RIwiTHS.  181 

The  hydra  feeds  on  the  larva?  of  insects.  Though 
less  iormidable  than  its  mythologic  namesake,  its 
natural  properties  aro,  to  say  the  least,  quite  as  re- 
markable. What  can  be  more  insignifioant  to  all 
ap[jearan(.'e  than  a  creature  so  small  that  its  thread- 
like body  cannot  very  well  be  studied  without  the 
aid  of  a  magnify isig-glass  or  a  microscope !  But 
what  more  curious  in  reality !  And  how  greatly 
has  the  discoverer  been  rewarded  for  his  devotion  to 
science  by  the  ever-increasing  importance  of  the 
facts  he  has  made  known!  It  is  thus  that  Nature 
rewards  the  labourers  who  devote  their  lives  to  the 
contemplation  of  her  marvellous  works. 

Hydras  proper  inhabit  the  fresh  waters ;  sea-wreaths 
or  sertularia?,  which  have  an  analogous  structure, 
are  well  known  to  those  observers  of  nature  who 
pursue  their  studies  on  the  shores  of  the  ocean. 
The  buds,  which  in  the  case  of  the  hydras  proper 
generally  detach  themselves  from  the  mother-stalk, 
remain  fixed  to  it  in  the  case  of  the  sertularian 
polypi.  The  result  is  that  a  horny  polypier  is  formed 
exteriorly,  not  interiorly,  the  polypi  being  enclosed 
in  the  orifices  of  the  horny  envelope.  The  latter 
also  assumes  the  most  varied  forms.  It  often  fixes 
itself  at  the  bottom  of  the  sea,  but  also  often  rests 
there  without  rooting  itself.  The  polypier  of  the 
hydra  proper  adheres  to  the  soil  by  its  base.     In  its 


182  THE  BOTTOM  OF  THE  SEA. 

perfection  it  may  be  compared  to  a  tree.  Marine 
plants  are  generally  attached  to  it,  and  at  its  ex- 
tremities are  stalks  analogous  to  those  of  flowers. 

One  entire  family  of  polyps  is  remarkable  for  its 
attachment  to  a  common  stalk,  which  is  capable  of 
supporting  the  colony  without  fixing  itself  to  the 
bottom  of  the  sea.  The  foot  buries  itself  in  the 
mud  or  sand,  or,  better  still,  the  polypier  floats  in 
the  water.  This  is  the  family  of  pennatulae,  of  which 
we  will  mention  only  three  examples — the  pennatula, 
the  virgularia,  and  the  veretillum. 

The  virgularia  has  a  rough  resemblance  to  a  pen. 
The  polypier  is  in  the  form  of  a  cylinder  split  length- 
wise. The  principal  stem  does  not  itself  bear  any 
polypi,  but  they  are  attached,  like  blossoms,  to  the 
short  lateral  branches  which  proceed  from  the  stem 
at  equal  distances  from  the  top  of  the  polypier  almost 
to  its  other  extremity. 

The  Fennatula  s^jpinosa  (fig.  32)  is  destitute  ot 
polyps  over  the  greater  part  of  its  surface.  They  are 
arranged  to  the  right  and  left  of  a  large  stem,  upon 
fan-like  branches.  The  foot,  which  serves  to  fix 
the  polypier  in  the  sand,  is  shaped  like  the  hilt  of  a 
sword. 

In  the  Veretillum  cijnomorium  (fig.  33)  the  polypi 
are  arranged  with  great  regularity  over  the  greater 
part  of  the  polypier.     They  are  inserted  directly  in 


TENNATULM. 


183 


the  fleshy  matter  which  fills  the  interior  of  the  common 
stalk.  A  cylindrical  prolongation  of  the  stalk  serves, 
as  in  the  Pennatida  spinosa,  for  the  instantaneous 


Fig.  32. — Sea-pen  ^Pennatulaspinosa).  Fig.  33.'^Veretillum  Cynomoruim. 

mplantation  of  the  entire  colony  in  the  place  chosen 
for  its  residence. 


184  THE  BOTTOM  OF  THE  SEA. 

The  pennatulsB  rank  with  animals  which  are  gene- 
rally phosphorescent — that  is  to  say,  which  emit  liglit 
in  the  night.  They  abound  most  near  the  shores 
of  European  seas.  Cuvier  gave  them  the  name  of 
"  swimming  polypi "  {Polypes  oiageurs). 


8.  ActinisB—  Sea-Anemones— Sea-Nettles. 

The  actinse,  or  sea-anemones,  though  independent 
(•reatures,  attach  themselves  firmly  (and  for  a  con- 
siderable length  of  time  without  changing  their 
locality)  to  the  rocks.  Adhesion  is  effected  by 
means  of  a  laige  and  fleshy  base,  which  secretes  a 
glutinous  matter,  and  it  depends  entirely  on  the 
will  of  the  animal.  It  moves  from  one  situation  to 
another  when  it  pleases,  using  its  tentaculse  as  feet, 
or  gliding  along  at  the  bottom  of  the  sea  by  a  move- 
ment which  can  scarcely  be  perceived. 

The  actiniae  appear  under  the  most  varied  aspects, 
owing  to  the  innumerable  modifications  of  which  the 
tentaculae  are  susceptible,  and  to  the  diversfied  cha- 
racters of  the  loot  itself.  We  may  compare  one  of 
these  creatures  to  a  flower  plunged  in  water,  with 
petals  so  soft  and  flexible  that  they  yield  to  its 
slightest  movements.  At  one  moment  they  may  be 
seen  gathered  together  to  agitate  the  water,  as  a 
iQcans  of  renewing  its  freshness  before  the  mouth 


ACTINTJE.— SEA-NETTLES.  185 

which  they  protect ;  at  another  they  contract  and 
disappear  before  some  threatened  danger,  or  they 
stretch  themselves  out  to  seize  their  almost  invisible 
prey. 

The  exterior  surface  of  the  actinaria  is  thickly  set 
with  oblong  lance-shaped  prominences,  terminating 
in  a  stylet,  rigid  and  sometimes  barbed,  to  wliich  is 
probably  due  the  burning  sensation  produced  by  their 
contact.  It  is  from  that  sensation  that  this  species  of 
polyps  has  derived  tlie  name  of  sea-nettles.  They 
have  been  called  anemones,  from  their  resemblance  to 
that  beautiful  flower,  and  actinia  (starlike)  from  the 
rays  or  tentacles  which  surround  the  mouth. 

The  coralline  polyps  are  all,  like  the  actinaria, 
armed   with  spiculaj,  of  which  the  forms  are  most 
varied,  according  to  the  species.    Fig.  34 
shows   the    general   character  of  these 
spiculae.    The  body  of  the  actinia,  almost 
cylindrical  when   extended,  is  contrac- 
tile.     It   becomes   globular,   or  almost 
spherical,  when   the    animal  is    folded 
back   upon    itself.      Its    tentacles    are        Fig.  3L 
then  contracted,  and  almost  completely        '^^^"^^  ' 
covered   by  the  tough  envelope  of  the 
body.    When  extended  they  serve  to  arrest  by  simple 
contact  the  little  marine  animals  which  touch  them. 

The  actinia;  do  not  reside  in  great  depths.     They 


186  TEE  BOTTOM  OF  THE  SEA. 

are  generally  found  attached  to  rocks  in  the  neigh- 
bourhood of  coasts.  They  are  almost  all  useless,  but 
one  species  is  eaten  in  Provence  and  at  Nice.  It  is 
very  soft  and  of  a  greenish  colour,  with  brown  stains 
on  the  body.  The  extremities  of  its  tentaculse,  often 
very  long,  are  frequently  of  a  pinkish  hue. 

These  animals,  unlike  coralline  polyps,  are  nearly 
always  found  separate  from  other  individuals  of  their 
species.  While  other  polypi  are  for  the  most  part 
bound  to  their  native  place,  the  actinaria  are  free  to 
choose  their  abode,  and  change  it  at  pleasure. 


9.  Coral — Miraculous  virtue  attributed  to  Coral  by  ancient  tradi- 
tion— Coral  Stone— Coral  Plant — Marsigli  discovers  the  Flowers 
of  the  Coral — Observations  of  M.  Lacaze-Duthiers. 

One  of  the  most  interesting  of  the  fixed  polypi  is, 
without  doubt,  the  coral.  Naturalists  of  ancient 
times  regarded  it  as  a  stone,  or  as  the  solid  axis  of  a 
marine  plant.  Dioscorides  thought  it  to  be  a  marine 
shrub  which  hardened  on  being  taken  out  of  the  sea 
and  exposed  to  the  air.  He  even  thought  it  petrified 
if  touched  while  it  was  alive  in  the  water.  In  1585, 
the  Chevalier  J.  B.  de  Nicolai,  previous  to  fishing 
coral  on  the  coasts  of  Tunis,  persuaded  a  fisherman 
to  dive  for  the  purpose  of  ascertaining  whether  the 
coral,  in  situ,  was  hard  or  soft.      Contrary  to  the 


NATURE  OF  CORAL.  187 

opinion  of  ancient  times,  this  man  reported  that  it 
was  hard.  Nicolai,  resolved  to  be  sure  of  the  fact, 
dived  himself,  and  ascertained  the  truth  of  the  man's 
statement. 

In  1671,  an  Italian  naturalist  decided  that  as  coral 
had  neither  flowers  nor  leaves,  nor  seeds  nor  fruits, 
it  ought  to  be  classed  with  stones.  This  idea  seemed 
aU  the  more  strange,  considering  that  after  the  time 
of  Nicolai,  a  Lyonnese  gentleman,  named  Poitier, 
had  observed,  in  1613,  the  presence  of  a  milky  juice 
in  fresh  coral,  and  had  demonstrated  that  it  >vas  only 
necessary  to  remove  a  kind  of  crust  to  give  it  the 
polish  and  the  red  colour. 

Marsigli,  in  1706,  announced  to  the  Academy  of 
Sciences  that  he  had  discovered  small  white  bodies, 
like  flowei-s,  on  the  surface  of  the  coral.  So  long  as 
he  left  the  branch  of  coral  in  sea-water,  the  flowers 
remained  expanded;  but  they  instantly  closed  when 
the  coral  was  taken  from  the  water,  reappearing  as 
instantly  when  it  was  replaced.  Without  investigat- 
ing whether  these  might  be  animals  or  not,  Marsigli 
concluded  that  the  coral  was  a  plant. 

The  merit  of  having  discovered  the  true  nature  of 
coral  belongs  exclusively  to  a  Frenchman,  Jean 
Andre  de  Peyssonnel,  a  physician  and  botanist,  whose 
observations  were  made  on  the  coasts  of  Provence  and 
Barbary,  at  the  instance  of  the  Academy  of  Sciences. 


188  THE  BOTTOM  OF  THE  SEA. 

Tlie  Museum  of  Natural  History  at  Paris  possesses' 
the  unprinted  manuscripts  wliicli  contain  the  results 
of  his  studies  of  the  nature  of  coral,  and  of  many 
zoophytes.  He  demonstrates  that  the  coral  branch 
is  an  aggregation  of  animalcules,  and  he  compares 
them  to  the  sea-nettles,  whose  name  was  already 
known.  "I  have  had,"  he  says,  *'the  pleasure  of 
seeing  removed  the  claws  or  feet  of  that  nettle,  and 
having  put  the  vessel  of  water,  in  which  the  coral 
was  placed,  over  a  fire,  all  the  animalcules  expanded. 
I  stirred  the  fire  and  caused  the  water  to  boil,  when 
the  creatures  came  out  of  the  coral  precisely  as  when 
one  cooks  any  kind  of  shellfish."* 

This  discovery  was  opposed  to  so  many  prejudices 
that  it  was  badly  received  for  some  time.  Eeaumiir, 
whose  name  was  then  all-powerful  in  science,  ex- 
pressed ironically  his  dissent,  without  having  in  the 
least  attempted  to  test  the  researches  of  Peyssonnel, 
and  this  probably  prevented  the  publication  of  a 
manuscript  which  would  be  well  worthy  of  being 
rescued  from  oblivion. 

Numerous  other  labours  in  this  field  of  research, 
among  which  those  of  M.  Lacaze-Duthiers  may  be 
mentioned  as  not  the  least  remarkable,  have  made 
us  pretty  well  acquainted  with  the  nature  of  coral. 
It  results  from  the  interior  hardening  of  a  polypier, 

*  T^ait^  du  Corail 


VARIETIES  OF  CORAL.  ISrv 

or  colony  of  polyps.  The  supposed  crust  is  simply 
the  newest  part,  and  as  it  has  not  acquired  tho 
consistency  of  the  interior  mass,  it  is  not  capable 
of  being  utilised  commercially.  The  polypi  are 
lodged  in  the  little  cavities  or  hollows  of  that 
crust,  which  they  secrete,  an  1  which  serves  them  for 
support. 


10.  Coral  chicrty  found  in  the  Meditermnefln  Sea — Various  speeiea 
of  Coral — The  Coral  Fishery — Antipathus,  cununonly  called 
Black  Coral. 

The  coral  of  which  we  are  here  to  speak  is  that 
beautiful  production  of  the  seas  with  which  ladies  are 
familiar  among  their  elegant  articles  of  bijouterie,  not 
the  masses  which  form  coral  reefs  in  the  Pacific 
Ocean.  It  is  found  in  the  Me  literranean  chiefly,  but 
also  in  the  Red  Sea.  Its  chief  habitats  are  in  the 
neighbourhood  of  MarseilL's,  on  the  coasts  of  Corsica* 
►Sardinia,  Sicily,  the  Balearic  Isles,  and  near  Tunis 
and  La  Calle.  The  last-mentioned  locality  has  for  a 
long  time  sup|)lied  the  greater  part  of  the  coral  of 
commerce.  It  is  fixed  to  the  rocks  by  an  enlarge- 
ment of  its  base.  The  fishers  state  that  its  dimen- 
sions grow  less  in  proportion  as  the  depth  at  which  it 
is  found  increases.  It  is  generally  fislied  in  com- 
paratively shallow  watei-s,  ranging  from   ten   to  fifty 


190  THE  BOTTOM  OF  THE  SEA. 

yards,  and  is  never  taken  at  greater  depths  than  frorc 
200  to  350  yards. 

The  colour  of  coral  is  generally  a  beautiful  red, 
but  it  is  found  of  every  intermediate  tint  between 
red  and  white.  That  fished  on  the  coasts  of  France 
owes  its  celebrity  to  the  richness  of  its  colours.  The 
different  kinds  are  known  to  commerce  under  the 
various  names  of  "blood  coral,"  first,  second,  and 
third,  &c.,  according  to  the  shade.  White  coral  is 
but  little  esteemed,  if  we  except  that  kind  known  as 
"  cornelian- white." 

The  coral  fishery  is  chiefly  in  the  hands  of  the 
Maltese,  but  it  is  also  pursued  by  the  Italians  and  the 
French.  An  idea  of  the  manner  in  which  it  is 
practised  on  the  coasts  of  Sicily  will  not  be  unin- 
teresting to  the  reader.  The  little  fleet  engaged  in 
the  fishery  consists  of  small  barks,  attended  by 
boats  which  are  manned  by  three  or  four  men,  who 
take  up  various  positions  over  the  coral  bank.  The 
tackle  used  is  a  kind  of  drag  with  arms,  worked  by 
means  of  a  capstan.  Each  branch  or  arm  of  the  drag 
has  a  kind  of  netted  sack  at  the  end  of  it,  into  which 
the  coral  falls  as  it  is  broken  off.  Beneath  the  centre 
of  the  cross  formed  by  the  arms,  a  heavy  stone  is 
swung;  and  the  whole  apparatus  is  dragged  along 
the  rocky  bottom  by  the  forward  motion  of  the 
vessel  and  the  lifting  motion  of  the  capstan  operated 


THE  GOBOONIDJE,  191 

at  the  same  time.  When  the  drag  is  pulled  on  deck, 
tlie  available  coral  is  selected  from  the  mass  and 
cleansed  for  sale.  The  occupation  is  a  very  laborious 
one,  more  especially  as  it  is  pursued  under  the  burn- 
ing sun  of  the  Mediterranean. 

Black  coral,  so  called,  is  the  stalk  of  a  poly- 
pier  of  another  species,  called  the  antipathos.  The 
polyps  are  very  small,  and  have  six  tentaculae;  in  the 
middle  of  them  is  the  only  opening  of  the  creature's 
body,  the  internal  texture  of  which  is  analogous  to 
that  which  we  have  already  described  as  common  to 
polypi  in  general.  It  derives  a  certain  commercial 
value  from  the  fact  that,  in  drying,  the  centre  and 
hardened  part  of  the  st^ilk  completely  sheds  the 
cortical  envelope  and  the  polypi  attached  to  it. 


II.  Gorgons  of  the  old  writers — Their  animal  nature  discovered  by 
Peyssonnel,  Trembley,  and  Bernard  de  Jussieu— The  Fau 
Gorgon — Its  cosmopolitan  character. 

The  gorgons,  so  named  by  Pliny,  were  originally 
taken,  like  other  polypiers,  for  marine  plants.  Even 
yet,  we  are  not  thoroughly  acquainted  with  their 
manner  of  life.  By  means  of  the  microscope,  the 
naturalists  of  the  last  two  centuries  have  been  able 
to  demonstrate  the  existence  of  these  polyps,  which 
iiua  been  legardea  as  iiowers.    PeyssuULel,  i  rembley. 


102  THE  BOTTOM  OF  TEE  SEA. 

and,  above  all,  Bei-nard  de   Jussieu  and  Giiettard, 
have  demonstrated  their  animal  nature. 

Tlie  polypier  is  Hexible,  in   consequence  of    not 


Fig.  35. — Portion  of  the  Fan  Gorgon,  magnified. 

being  entirely  stony.       It  has,  therefore;  not  been 
utilised     in    the    arts.        It    has,    however,    been 


GORGON  I A  VERTICELLATA.  103 

employed  in  the  construction  of  small  objects  requir- 
ing a  substance  at  once  hard  and  elastic. 

Gorgons  live,  like  otlier  marine  polyps,  at  the 
bottom  of  the  sea,  or  upon  marine  bodies  to  which 
they  attach  themselves.  As  is  the  case  with  the 
coral  and  the  antipathidae,  a  great  number  of  indi- 
viduals live  upon  the  same  polypier.  The  body  is 
retractile.  Generally,  it  is  small  ;  and,  for  many 
species,  a  maguifying-glass  is  necessary  to  distinguish 
clearly  the  animal  from  the  living  fleshy  crust  which 
surrounds  the  polypier. 

The  portion  of  the  fan-gorgon  represented  in  fig. 
35,  shows  the  polypi  in  the  form  of  small  roiuid 
tubercles  with  a  hollow  in  their  centre.  The  pol3^pi 
are  still  more  apparent  in  the  whorled  gorgon  {Gor- 
gonia  verticdlata).  This  species  has  been  so  named 
because  the  polyps  are  grouped  at  different  points  of 
the  stalk,  and  form  at  ( a(^h  of  those  points  a  whorl  of 
animals  all  round  the  branch.* 

The  gorgonidsB  display  the  most  beautiful  colours 
in  the  sra,  but  tl.eir  hues  fade  soon  after  they  have 
been  tfiken  from  the  water,  and  retain  only  the  pale 
sliadows  of  white,  black,  red,  green,  violet  or  yellow, 
8  ich  as  vvc  see  in  the  collections. 

*  The  word  vert'cellated  is  i  rai)loyed  by  botanists  to  designate  the 
grouping  of  leaves  which  gn.w  at  the  same  heigl.t  upon  n  bnmc.i 
around  which  they  f  rni  a  .^ort  of  crown.  — Tr. 


194  THE  BOTTOM  OF  THE  SEA. 

The  poly  pier  of  the  gorgonidoe  is  very  variously 
formed  in  the  different  species.  Sometimes  the 
branches  are  almost  straight,  as  in  the  vvhorled 
gorgon ;  sometimes  they  cross  and  interlace  in  a 
thousand  ways,  and  give  to  the  polypier  the  aspect 
of  network,  more  or  less  close. 

The  fan-gorgon  is  a  remarkable  example  of  this. 
The  enlarged  extremity  of  its  principal  stem,  denuded 
of  its  living  crust,  is  attached  to  the  rock.  From 
this  stem  spring  many  hard  and  naked  branches, 
which,  inteisecting  one  with  another,  pass  into  a  net- 
work in  which  the  polypi  live. 

In  size  the  gorgonidae  range  between  two  very 
distant  limits.  The  smallest  that  has  been  studied 
may  be  less  than  an  inch  in  height ;  others  reach 
many  feet.  Some  fragments  have  been  seen  by  the 
writer,  which  show  that  the  entire  individual  was  of 
still  more  considerable  dimensions. 

These  animals  live  at  a  great  depth,  and  inhabit 
every  sea.  The  fan-gorgon  is  more  generally  dis- 
tributed than  any  other.  They  most  abound  in  the 
warmer  waters,  as  is  the  case  with  other  species  of 
polyps. 


CALCAREOUS  POLYPIERS.  195 


12.  The  more  iictivo  Biibmarine  constructors  -  Astroides  —  Caryo- 
plnllia— Madrc'poraPlanta^'inea — Dcmlrophyllia — Occulinn,  or 
Wliite  Coral — Mean  Irina — Fungia — Porites — Milleporse. 

The  purely  calcareous  polypiers  have  their  prin- 
cipal seat  in  tropical  regions.  These  are  the  species 
which  exercise  the  most  marked  influence?  upon  the 
varied  surface  of  the  sea-buttom,  and  which  have 
distinguished  themselves  as  the  constructors  of  reefs 
and  islands.  The  principal  types  of  this  class  of 
polypiers  are  the  caryophillia,  the  meandrina,  the 
fungia,  and  the  pentacrini.  For  a  long  time  th<  se 
species  were  confounded  together  under  the  generjil 
name  of  madrepores^  and  it  is  only  during  late  years 
that  their  polypi  have  been  recognised. 

These  polypi  bear  a  very  close  resemblance  to 
those  of  actinia?  and  corals;  but  the  foldings  wiiii  li 
we  have  remarked  in  tlie  digestive  cavity  are  not 
connected,  as  is  the  case  in  the  latter.  They  generally 
occur  at  the  base,  so  as  to  constitute  a  central  axis 
surrounded  with  ra  Hating  cells,  which  are  only  quite 
separate!  from  each  other  at  the  lower  part  of  the 
animal.  Their  similarity  to  the  actiniae,  already 
described,  is  apparent  at  first  sight.  In  proportion 
as  the  polypier  grows,  its  lower  part  becomes  cal- 
ciireous,  and  reproduces  in  stone  the  soft  structure 
that  had   bei  n  formed    by  the  living  animal.     The 


19G 


TEE  BOTTOM  OF  THE  SEA. 


divisious  of  the  fissures  or  cells  harden  gradually, 
owing  to  the  deposit  of  calcareous  matter  in  the 
interior  of  their  tissue.  It  forms  little  transverse 
plates,  which  close  the  bottom  of  the  cells,  bounded 
by  the  radiating  divisions.  When  the  polyp  dies, 
we  discover  at  the  bottom  of  the  place  which  it  oc- 
cupied a  stony  polypier,  divided  by  plates  which 
converge  towards  an  axis,  and  terminate  at  the  upper 
extremity  by  forming  a  little  starry  cup  (fig.  36). 


Fig.  3(5. — Deiidrophj'lli.i  Ramea. 

1.  Nntural  size,  with  polyps. 

2.  Magnified,  with  tlie  polyps  dead. 

The  difFcren(e  between  the  Viirions  polypi  of  this 
gnnp    consists  especially   in   their   mo.;e  of    repro- 


ASTJiEA  rUNCTIFERA. 


VSi 


tluction,  and  in  the  consequent  form  of  the  polypier 
which  thty  produce.  When  the  individuals  are 
isolated,  or  not  closely  grouped  (fig.  37),  the  poly- 
pier attains  no  great  dimensions.  The  caryophillia 
presents  this  character,  and  examples  of  them  are  to 
be  found  even  in  European  seas. 

In  other  varieties  the  buds  do  not  separate  them- 


rh/4^ 


Fig.  37. — Caryophillia  Cyatuus. 


pelves  from  tlie  original  stem,  but  remain  an  integral 
part  of  it  as  they  grow  in  number  and  size  (fig.  ^8). 
They  develope  side  by  side,  and  are  joined  one  to 
another  by  a  comj:act  tissue,  which  is  tlius  formed 
into  thick  masses.    The  polypier  is  espec  ially  charac- 


198 


THE  BOTTOM  OF  THE  SEA. 


terised  by  tlie  continuity  of  each  column  down  to 
the  base.  The  species  of  astrea  are  numerous,  more 
particularly  iu  the  neighbourhood  of  the  equator. 

When  the  buds  in  the  process  of  development  do 
not   remain    parallel   with   the   mother-branch,   the 


Fig.  38.— Astrea  Punctifera. 

polypier  takes  the  form  of  a  tree,  more  or  less  dis- 
tinctly. In  this  case,  the  name  it  bears  recalls  the 
ve:^etable  form  to  which  it  approximates.  The 
Madrejpora  jplantaginea  (fig.  39)  is  formed  by  the 
aggregation  of  small  polypi  joined  together  by  masses 
more  or  less  conical  in  form.  To  every  polypus  there 
is  a  corresponding  little  depression,  surrounded  with 
a  slight  eminence.  In  general  appearance  the  poly- 
pier with  its  polyps  resembles  a  spike  of  plantain. 


ARBORESCENT  POLTPIERS 


199 


A  deeper  separation  still  of  the  polypi,  as  well  as 
a  greater  amount  of  divergence  one  from  another, 
brings  us  back  to  the  arborescent  forms  assume  I  by 
the  coral. 


Fig.  39. — Madrepora  PLiutagiuea. 

The  dendrophyUia,   represented  half  the  natural 
size    (fig.  40),  has   a   massive   trunk,    l)y  which   it 


200 


THE  BOTTOM  OF  THE  SEA. 


seems  to  grow  out  of  the  rock  as  a  tree  out  of  iLe 
ground,  and  from  wbich  the  branches  proceed  in  all 
possible    directions.      At    the    extremities    of    the 


Fig.  40.— Dendiopl.yllia  (half  tl.e  natuinl  size). 

branches    are    the    cuplike    Jiollows    in    which    the 
polypi  live. 


OCCULINA  VIBGISEA.  IQ\ 

A  kindred  species,  the  occuUna,  is  remarkable 
for  the  excessive  subdivision  of  its  branches,  as 
well  as  for  their  arrangement.  The  polypi  are 
found  both  on  the  surface  of  the  stems,  and  at  their 
extremities,  and  every  one  of  them  gives  birth*  to 
a  new  branch — the  whole  constituting  a  very  ele- 
gant treelike  formation.  The  type  of  the  species 
is  the  Occvlina  virginea^  sometimes  called  white 
coral.  It  is  common  in  the  Mediterranean,  and  is 
also  found  in  the  neighbourhood  of  the  equator. 

No  such  symmetry  as  we  have  observed  in  the 
coralline  polypiers  is  to  be  found  in  the  meandrina, 
or  brain  coral,  of  which  there  are  some  fine  speci- 
mens in  the  British  Museum.  The  polyps  of  this 
species  have  no  tentacles  around  their  mouths,  but 
short  lateral  ones.  They  are  huddled  together  in 
the  shallow  sinuosities  which  furrow  the  surface  of 
the  polypier ;  but  sometimes  they  disappear  alto- 
gether, as  in  a  species  found  in  the  lied  Sea.  All 
that  can  be  discovered  in  the  furiows  is  a  row  of 
mouths.  The  sinuosities  vary  according  to  the 
s|)ecies.  Their  numerous  folds  wind  among  one 
tmother  like  a  maze,  reminding  one  of  the  famous 
Cretan  labyrinth ;  hence  the  name  given  to  this 
species  {meandrina,  meandering).  They  are  generally 
globular,  or  nearly  so,  in  form,  and  are  found  of 
various  sizes  on  isolated  rocks.     They  are  abundant 


202  THE  BOTTOM  OF  THE  BEA» 

in  the  Herl  Sea,*  but  are  still  more  frequent  in  the 
equatorial  seas,  where  their  size  and  their  general 
aspect  have  suggested  the  name  by  which  they  are 
sometimes  called  by  sailors — Nejptunes  Brain.  A 
specimen  in  the  British  Museum  is  four  feet  in  circum- 
ference. Their  great  size  is  accounted  for  by  the 
manner  of  their  formation.  "  As  one  fleshy  mass  ex- 
[)ires,"  observes  Dr.  Mantell,  "  another  appears  and 
gradually  expands,  pouring  out  its  calcareous  secre- 
tion on  the  parent  mass  of  coral :  thus  successive  gene- 
rations go  on  accumulating  vast  beds  of  stony  matter, 
and  lay  the  foundation  foi-  coral  reels  and  islands."  As 
remarked  in  Lyell's  *'  Principles  of  Geology,"  "  We 
may  compare  the  operations  of  the  zoophytes  in  the 
ocean  to  the  effects  produced  on  a  smaller  scale  on 
land  by  the  plants  which  generate  peat ;  in  which  the 
upper  part  of  the  sphagnum  vegetates,  while  the  lowt  r 
is  entering  into  a  mineral  mass,  in  which  the  traces  of 
organisation  remain  when  life  has  entirely  ceased.  In 
corals,  in  like  manner,  the  more  durable  materials  of 
the  generation  that  has  passed  away  serve  as  the 
foundation  on  which  their   progeny  are  continuing 

*  "  The  whole  bed  of  this  extensive  basin  of  water  is  absolutely 
a  forest  of  submarine  plants  and  coials.  Here  are  sponges,  madre- 
pores, corals,  fungise,  and  otlier  polyparia,  with  fuci,  algsB,  and  all 
the  variety  of  marine  vegetation,  covering  every  part  of  the  bottom, 
and  presenting  the  appearance  of  a  submarine  garden  of  the  most 
exqui-ite  verdure." — Mantell. 


TEE  MEAKDRINJE. 


20:5 


to   spread   successive   accumuJations  of    calcareous 
matter." 

'rhe  poriteSy  or  poritidie,  belong  to  the  same  group, 


Fit;.  41. — Mcaiidiiiia  Celeblilo^Illi^. 


nnd  are  amons:  the  number  of  polypiers  which  often 
attain  very  larc:e  dimensions.  Their  substance  is 
calcareous.  Their  surface  is  riddled  with  pores,  or 
rather  little  shnllow  cups,  in  which  the  living  polyps 


204 


thp:  bottom  of  the  ska. 


are  found.     Most  frequently  the  polypier  is  set  with 
polyps  from  its  foot  to  its  summit,  although  those  at 


fig.  42. — Millepora  Alcicornis  (one-fouith  of  the  natural  size). 


the  base  may  no  longer  be  living.  Each  of  these 
little  animals  is  marked  by  the  characteristics  which 
we  have  notice  1  more  than  once.     The  number  of 


TUK  FUNGIA.  205 

teutaele8  diff'ers  in  the  various  species,  and  is  ulten 
very  considerable. 

Wlien  the  polyps  are  removed  from  the  stem,  the 
little  hollows  with  their  imperfect  divisions  become 
visible  all  over  the  polypier.  The  latter  assumes  the 
most  varied  forms,  according  to  the  manner  in  which 
the  polyps  are  reproduced.  Sometimes  they  are  most 
com})lex  and  elegant,  as  in  the  case  of  the  Millepora 
alcicornis  (fig.  42). 

These  animals  differ  from  the  astroides  proper  in 
the  arrangement  of  their  polypi,  and  from  tiie  coral- 
lines in  the  absence  of  the  fleshy  incrustation  around 
the  polypier.  The  polypier  is  wholly  calcareous.  Its 
development  is  owing  to  the  hardening  of  the  trans- 
verse divisions  of  the  polypi  and  of  their  external 
covering.  Their  growth  is  irregular,  and  it  leaves  no 
trace  of  the  animals  themselves  except  the  irregular 
pores.  They  are  found  in  the  seas  of  the  North  and 
of  America. 

The  variety  of  entirely  calcareous  polypiers  is  very 
numerous.  One  in  particular  we  must  not  overlook — 
the  jungia,  so  called  from  its  resemblance  to  the  ve- 
getable fungi.  The  animal  of  this  species  is  gelatinous 
or  membranous,  somewhat  oval  in  form,  abd  much  flat- 
tened. The  engraving  (fig.  43)  represents  a  mouth  in 
the  centre  of  a  large  disc,  the  interior  of  which  is  made 
solid  by  a  calcareous  deposit,  while  the  solid  cure  is 


206 


THE  BOTTOM  OF  THE  St.A. 


covered  with  plates  or  lamellae,  radiati  ng  from  the  centre 
towards  the  circumference.  Protruding  from  the  disc 
are  a  great  number  of  tentacuke,  which  tlie  animal 


'  Fig.  43. — P''ungia  Agaricitontiis. 

contracts  or  extends  at  will  from  between  the  sharp, 
thin  plates  of  the  polypier.  At  the  end  of  each  ten- 
tacle a  sucker  is  represented ;  it  is  used  by  the  animal 
to  capture  its  prey» 


DESTHUCTION  AND  RENOVATION.  207 


13.  Gttiley-slaves  of  the  Sea— The  Giants  atitl  Pif^uies  i»f  Creation 
— The  Suckers — Legends  of  Monsters— Singing  Fishes. 

The  greatest  activity  prevails  beneath  the  surface 
of  the  sea.  Were  it  possible  to  lift  the  veil,  scfenes 
the  most  varied  and  unexpected  would  meet  our  gaze. 
Creatures  which  inhabit  the  deep  would  be  seen  in- 
cessantly labouring  to  renew  or  adorn  the  earth. 
Some  are  engaged  in  the  work  of  destruction,  some  in 
building  up.  The  one  class  supplies  the  other  with 
the  materials  which  it  fashions  into  forms  of  beauty. 

Among  those  we  have  called  destroyers,  thepholas, 
though  it  plays  an  obscure  part,  is  very  remarkable. 
It  does  not  browse  on  the  animal  flowers  of  the 
polypier.  It  does  not  play  the  part  of  a  tiger  in 
the  sea,  and  devour  armies  of  fish.  It  simply  eats 
its  way  into  the  hardest  stones,  as  the  xylophagi 
burrow  in  wood.  Even  the  hardness  of  gneiss  is 
not  proof  against  its  patient  determination. 

At  first  sight  we  should  be  disposed  to  say  that  no 
weapon,  no  tool,  aids  this  indefatigable  labourer. 
The  shell  has  two  valves  of  the  ordinary  character, 
turning  on  a  cartilaginous  hinge.  The  body  has  two 
openings.  Its  substance  is  capable  of  being  elongated 
80  as  to  form  a  tube  traversed  by  two  channels — one 
of  which  serves  for  the  absorption  of  water,  the  other 
^  eject  it  as  frpm  a  syringe,     The  soft  rounded  L'O ' v 


208  THE  BOTTOM  OF  THE  SEA. 

of  the  aininal  seems  to  be  furnished  with  no  organ 
by  which  oven  the  softest  substance  could  be  pierced. 
It  has  two  teeth,  but  they  are  so  deeply  seated  that  it 
is  impossible  they  could  ever  operate  upon  the  walls 
of  tlie  retreat  which  the  creature  bores  out  for 
itself.  Our  attention  is  directed  to  the  anterior  part 
of  the  shell,  which  appears  to  be  set  with  hard  points, 
so  arranged  on  the  surfaces  extending  from  the  hinge, 
forward,  as  to  form  a  kind  of  file.  At  this  end,  a 
short  foot  or  tongue  is  protruded,  by  which  the  ani- 
mal holds  on  to  the  rock,  while  at  the  same  time  it 
partly  turns  itself,  and  thus  by  the  friction  of  the 
serrated  shell  rasps  away  the  chalk  or  rock.  The 
work  commences  from  the  beginning  of  the  creature's 
life.  It  iirst  makes  a  slight  hollow  in  the  stone,  in 
which  it  ensconces  itself.  In  that  position  the  water 
of  the  sea  brings  it  sufficient  food.  Little  by  little, 
as  the  animal  grows,  it  enlarges  the  shell  in  which  it 
lives,  and  at  the  same  time  buries  itself  more  deeply 
in  the  stone.  Their  advance  is  made  almost  horizon- 
tally at  Iirst ;  but  having  reached  a  certain  depth, 
they  suddenly  change  their  direction,  and  bore  out 
their  ret  i  oat  perpendicularly.  It  is  at  once  theil 
dwelling  iind  their  tomb,  and  in  form  resembles  a 
common  tobacco-pipe — the  stalk  debouching  in  the 
sea,  and  the  bowl  containing  the  animal. 

In  the  regions  frequented  by  pholades,  the  rocks 


are  thus  pierced  in  every  direction.  We  even  see 
enormous  stones  bored  quite  througii,  from  side  to 
side,  by  these  destroyers.     It  was  for  a  long  time  be- 


ti^i^C 


Fi>,  44. — Gneiss  bored  by  the  Pbolndes  Dnctylns. 

lieved  that  they  effected  their  lodgment  while  the 
ror»k  was  in  a  soft  state,  and  that  it  afterwards  grew 
har^l  around  them,  and  enclosed  them  as  in  a  living 
tomb,  owinpr  to  the  petrifying  virtue  of  the  water. 


210  mt!  JiOTTOM  OF  TtlP.  SEA. 

This  opinion  was  abandoned  when  it  was  observed 
that  the  columns  of  the  ancient  temple  of  Serapis,  at 
Pozzuolis,  which  had  been  submerged  for  many  years 
in  consequence  of  an  earthquake,  and  again  restored 
to  the  light  of  day,  had  been  pierced  all  over  by 
pholades. 

Shut  up  in  a  prison  from  which  they  can  never 
make  their  escape,  these  galley-slaves  of  the  sea  con- 
tinue their  work  of  destruction  to  the  end  of  their 
lives,  and  they  have  only  themselves  to  blame  for 
their  perpetual  seclusion  from  society.  Without  the 
least  care  for  the  morrow,  they  go  on  boring  their 
way  through  the  rock,  enlarging  themselves  and  their 
stony  habitation  as  they  advance  farther  from  the  sea. 
The  open  end  of  this  singular  gallery  is  the  gate  by 
which  the  sea  washes  in  all  that  these  animals  need 
for  their  nourishment,  and  for  which  the  pholas  re- 
pays tlie  ocean  in  a  perpetual  tribute  of  dust.  Every 
wave  carries  something  into  the  mine,  and  brings 
something  away — another  and  very  striking  example 
of  the  universal  work  of  sedimentation. 

Rocks  too  hard  to  be  breached  by  the  ^vaves  them- 
selves, are  thus  eaten  away  and  scattered  on  the  floor 
of  the  ocean  by  the  pholades.  For  others  are  the 
transparent  waters,  the  romantic  ocean  ravines,  or 
the  extended  plains  of  sand  and  mud.  The  oyster 
the  sol  en,  and  the  razor-fish  linger  in  agreeable  situa- 


VttOSVnonESCENCK  OF  TItK  PUOUS.  211 

tions,  and  enjoy  abundance  of  water  privilege.  Tlie 
pholades,  like  other  molluscs,  exist  in  numerous  colo- 
nies, but  all  the  members  of  this  great  family  obey 
the  word  of  command.  Their  mission  is  to  go  for 
ever  forward,  extending  or  enlarging  their  mine,  and 
leaving  off  work  only  when  they  die.  Thus  employed, 
their  whole  lives  would  be  passed  in  darkness,  if 
nature  had  not  provided  every  one  of  these  little 
miners  with  a  lamp.  The  pholades  are  phospho- 
rescent. 

This  fact  was  remarked  by  Pliny,  but  the  cause  of 
the  phenomenon  remained  long  unknown.  Keaumur 
observed  that  if  he  washed  his  hands  after  touching  a 
pholas,  the  water  became  phosjjhorescent ;  and  at  the 
end  of  a  certain  time  the  phosphorescent  matter  fell 
to  the  bottom  of  the  vessel.  We  now  know  that  the 
phosphorescence  is  due  to  a  liquid  continually  secreted 
by  the  body  of  the  animal. 

In  contrast  with  these  pioneers  of  the  ocean,  of  these 
slaves  who  precede  and  assist  him  in  the  destruction 
of  continents,  there  is  a  creature  whose  fate  it  is  to 
float  incessantly  in  the  water,  at  the  mercy  of  the 
most  capricious  winds  and  currents.  We  have  already 
seen  (in  the  chapter  on  the  Colour  of  the  Ocean)  that 
the  water  holds  in  suspension  a  mass  of  microscopic 
beings.  It  is  to  the  existence  of  these  creatures  that 
is  due  the  yellowish  milky,  red,  or  olive-green  tint 


212  tUK  BOTTOM  OF  TBM  8EA. 

so  frequently  observed.  Freyssinet  and  Turrel  ob- 
served, near  the  shores  of  Luzon,  an  extent  of  some 
sixty  millions  of  square  yards  coloured  a  bright 
scarlet.  This  tint  was  owing  to  the  presence  of  an 
organisation  so  small  that  forty  millions  of  individuals 
occupied  the  space  of  a  square  millimetre.*  As 
the  discoloration  extended  to  a  considerable  depth, 
it  would  be  impossible  to  form  even  an  approximate 
idea  of  the  number  of  living  beings  which  caused  it. 

Some  of  these  microscopic  creatures  never  develope 
to  anything  beyond  a  little  cell  surrounded  with  vi- 
bratory cilise,  unequally  distributed  over  the  surface, 
and  serving  the  creature  either  as  rowers  or  as  an 
organ  for  continually  renewing  the  water  which  sur- 
rounds it  by  creating  a  current.  Their  mode  of 
reproduction  is  extremely  simple,  and,  at  the  same 
time,  admits  of  their  propagation  with  almost  frightful 
rapidity.  About  the  middle  of  the  creature  the  body 
contracts  like  the  division  between  the  two  parts  of 
an  insect,  and  the  contraction  increases  until  it 
separates  into  two.  Each  part  goes  through  the 
same  process  as  its  parent,  continually  dividing  into 
new  creatures,  until  in  about  twenty  generations  a 
single  infusoria  may  have  engendered  more  than  a 
million.  One  generation  succeeds  another  very 
quickly.    If,  then,  a  variety  of  causes  did  not  conspire 

*  A  millimotro  is  OoOSTths  of  an  inch. 


GlANTS  AND  PtomPJS.  21 H 

io  check  their  increase,  the  infiisorife  would  long 
since  have  filled  the  world. 

When  the  body  of  the  animal  is  soft  without  any- 
calcareous  addition,  we  find  no  traces  at  the  bottom 
of  the  sea  of  their  short  existence.  But  many  species 
are  furnished  with  a  sort  of  shell,  the  debris  of 
which  constitutes  the  greater  part  of  the  sand  formed 
on  the  ocean-bottom. 

The  foraminifersB  contribute  largely  in  conjunction 
with  the  infusorise  to  the  levelling-up  of  the  sub- 
marine valleys.  Their  microscopic  remains  —  not 
very  long  known  to  be  so,  indeed — occur  in  such 
enormous  masses  that  no  part  of  the  earth's  crust  is 
of  greater  interest  to  the  geologist. 

If  we  compare  with  the  whale,  the  shark,  and  other 
giants  of  the  creation,  the  modest  infusoria),  the  fora- 
miniferae,  and  the  Noctiluca  miliaris,  of  which  we  find 
as  many  as  25,000  individuals  in  thirty  cubic  centi 
metres  of  water,  we  shall  be  disposed  to  attach  very 
little,  if  any,  importance  to  the  infinitely  little.  The 
giant  attracts  our  eyes  by  his  mass  and  his  force, 
while  we  often  strive  in  vain  to  see  the  pigmies  of 
creation,  as  we  should  look  in  vain  for  an  atom  of 
dust  blown  by  the  wind.  The  giant,  however,  will 
pass  away,  leaving  but  few  traces  of  his  existence. 
Here  and  then;  a  bone  or  a  tooth,  perhaps  a  foot- 
print,  informs  us  of  the  fact  that  a  monster  onoe 


214  TJIF  nOTTOM  oP  THE  SEA. 

existed  whose  remains  have  long  been  the  sport  of 
tlie  waves.  The  pigmies,  feeble  when  taken  singly, 
are  powerful  in  their  multitude.  There  are  great 
animals  in  the  ocean,  but  the  armies  of  the  infinitely 
little  count  by  millions.  The  giants  of  the  deep 
make  their  presence  felt  while  they  live ;  the  pigmies 
of  creation  are  the  true  world-makers. 

Tlie  first  specimens  of  infusoriae  were  taken  from 
the  bottom  of  the  sea  by  the  apparatus  of  Brooke, 
when  the  submarine  plateau  upon  which  reposes  the 
telegraphic  cable  between  Newfoundland  and  Irelanl 
was  under  investigation.  The  appearance  presented 
to  the  eye  was  argillaceous,  but  the  celebrated  Pro- 
fessor Bailey,  of  West  Point,  having  studied  the  speci- 
mens with  the  aid  of  microscopes,  recognised  numerous 
calcareous  shells  in  a  state  of  perfect  preservation. 

The  average  depth  of  the  telegraphic  plateau  is 
something  under  10,000  feet.  That  depth,  though 
considerable,  and  exceeding  the  supposed  thickness 
of  the  submar  ine  vital  zone,  is  far  from  marking  the 
limits  of  the  empire  of  the  foraminiferae.  Where 
they  cannot  live,  their  spoil,  so  light,  is  carried  by 
the  ocean-currents,  and  deposited  in  obedience  to  the 
ordinary  physical  laws.  Specimens  obtained  by 
soun  lings  made  between  North  America  and  Asia 
have  demonstrated  the  presence  of  their  calcareous 
sholls  at  depths  px^feding  6000  yards. 


DEBHIS  OF  THS  iNFUSoMtM  215 

If  we  reflect  that  the  sand  of  the  seas  is  often 
almost  entirely  composed  of  these  little  shells,  so 
variously  and  elegantly  formed ;  if  we  remember 
that  they  have  been  accumulated  by  the  action  of 
marine  currents  in  regions  where  their  force  is  re- 
laxed, that  their  debris  meets  with  conditions  favour- 
able to  their  preservation  in  the  calm  deeps  of  ocean, 
who  will  not  marvel  at  the  enormous  influence  they 
exercise  upon  the  distribution  of  the  waters  upon 
the  surface  of  the  globe  ?  Yet  we  may  state,  on  the 
authority  of  M.  Alcide  d'Orbigny,  that  many  of 
these  creatures  do  not  exceed  one-half  or  one-sixth 
of  a  millimetre  in  dimensions.  The  same  authority 
states  that  he  has  found  30,000  individuals  in  half 
an  ounce  of  fine  sand  brought  from  the  Antilles,  or 
thirty  millions  in  a  kilogramme.  Another  learned 
naturalist,  Plancus,  has  counted  about  200,000  in 
a  pound  of  sand  from  the  Adriatic. 

The  creative  power  is  more  wonderfully  manifested 
in  these  small  beings  than  in  the  great.  The  com- 
plicated organs  and  the  harmonious  richness  of  the 
most  powerful  mechanical  appliances  impress  us  in 
the  giants  of  creation.  Our  astonishment  is  greater 
still,  perhaps,  in  face  of  the  pigmies.  The  sea,  in 
fact,  is  full  of  surprises.  We  imagine  all  that  is 
mysterious  beneath  its  waters.  The  furious  tempests 
which  disturb  its  surface  and  lash  the  air  seem  to 


2ir.  ftiE  BOTTOM  OF  THE  SMA. 

assign  a  limit  to  the  habitable  world.  "  The  sea  and 
all  that  therein  is  "  appears  surrounded  with  a  poetic 
and  miraculous  aureole,  which  is  the  birth  at  once  of 
fear  and  of  superstition. 

Before  our  ancestors  had  dared  to  launch  out  upon 
the  boundless  ocean,  the  Mediterranean  and  its  shores 
were  the  abode  of  the  marvellous.  As  man  extended 
the  bounds  of  his  empi  re,  the  region  of  wonder  and 
superstition  also  gradually  enlarged  itself.  Old  records 
show  that  the  Spirit  of  the  Storms  demanded  its 
victims  of  the  first  navigators  who  doubled  the 
dreaded  Cape  of  Good  Hope;  monsters  the  most 
hideous  or  grotesque  were  supposed  to  haunt  the 
coasts  of  Norway;  and  the  bottomless  Maelstrom 
had  its  genii  like  the  rocks  of  Scylla  and  Cha- 
ry bdis. 

Popular  tradition  pointed  to  the  existence  of 
islands  situated  far  away  to  the  westward.  The 
report  went  that,  after  the  conquest  of  Spain  by  the 
Arabs,  a  certain  number  of  Christians  put  to  sea,  and 
found  refuge  in  the  legendary  islands,  where  they 
built  seven  cities.  At  the  time  of  Columbus  this  sup- 
posed country  bore  the  reputed  name  of  Sette  Ciiade, 
and  was  called  by  geographers  Antilia,  which  name 
appears  on  the  niaps  down  to  the  end  of  the  fifteenth 
century — together  with  that  of  another  great  island, 
situate  in  the  latitude  of  Newfoundland,  and  called 


LEiiENDAHY  MARINE  MONSTEWS.  217 

the  hie  of  Satan,  According  to  Arab  tiaditious,  a 
great  hand  rose  every  night  from  the  sea,  near  the 
latter  island,  and,  seizing  the  inhabitants,  plunged 
them  into  a  dark  abyss.  Myths  of  the  highest  anti- 
quity refer  to  the  Atlantic  Ocean  as  the  abode  of  the 
blest  and  the  kingdom  of  the  dead,  and  traces  of 
these  legends  are  preserved  even  to  the  present  day 
in  Scotland  and  Ireland. 

On  a  certain  occasion  a  fishing-boat,  in  the  northern 
seas,  was  engaged  in  the  fishing  of  bishop-fish  and 
monk-fish.  The  kraken,  a  monster  of  many  square 
leagues  in  size,  rose  from  the  bottom  of  the  sea  ;  the 
vessel,  receiving  a  shock  as  if  it  had  struck  on  a  rock, 
was  sunk  with  all  its  crew  and  equipage. 

Another  form  of  monster,  dreaded  by  the  fearful 
and  superstitious,  had  immense  suckers  and  arms ;  a 
huge  mouth  in  the  midst  of  his  tentaculae  swallowed 
all  that  he  could  seize ;  his  arms  were  supposed  to 
be  hundreds  of  feet  in  length,  and  so  powerful  that 
they  could  enfold  and  crush  ships  of  considerable 
size.  The  gigantic  poulpe,  or  devil-fish,  and  the  sea- 
serpent,  have  been  the  subjects  of  the  most  marvel- 
lous stories,  which  in  our  day  have  been  reduced  to 
their  just  value.  These  terrible  monsters  generally 
resolve  into  immense  cordons,  or  vast  fields  of  alga?, 
interlaced  one  with  another,  and  waving  hither  and 
thither  at  the  mercy  of  every  breath  of  wind  which 


218  THE  BOTTOM  OF  THE  bEA. 

stirs  the  waves,  or  with  the  feeblest  motion  of  the 
ocean-currents. 

The  giant  poulpe  has  yet  to  be  discovered.  We 
find,  indeed,  on  rocky  coasts,  in  the  rugged  fis- 
sures and  caverns  of  the  ocean,  the  well-known  devil- 
fish, hideous  enough  truly,  resembling  a  sack  with 
serpent-like  arms  surrounding  a  horrible  mouth. 
With  these  arms  the  poulpe  seizes,  his  prey  in  a  far 
from  agreeable  embrace,  and  sucks  him,  as  a  spider 
does  a  fly,  before  swallowing  him,  so  as  to  enjoy  at 
his  ease  the  juicy  flesh  of  his  struggling  victim. 
These  horrible  creatures  will  sometimes  attack  man, 
though,  generally  speaking,  they  avoid  him.  In  all 
the  recorded  instances,  however,  the  danger  and  the 
horror  have  been  exaggerated.  An  adventurer  bold 
enough  to  thrust  his  arm  into  one  of  these  glutinous 
sacks  may  turn  it  inside-out  like  a  glove,  and,  con- 
trary to  what  we  have  observed  in  the  fresh-water 
hydra,  the  marine  monster  will  not  survive  the  opera- 
tion. In  one  other  respect  it  is  very  inferior  to  the 
hydra  of  mythology,  for  its  arms  are  very  far  from 
possessing  the  power  of  recoil  after  a  wound ;  if  they 
are  separated  from  the  trunk,  the  collapse  is  instan- 
taneous. 

The  calmars  appear  to  reach  much  larger  dimen- 
sions than  the  poulpes  :  they  are  sufficiently  formid- 
able to  be  dreaded  hj  the  Siivages  who  traverse^  'u\ 


THE  CALMAR.~THE  RAY.  219 

their  light  canoes,  the  waters  whicli  they  frequent. 
These  animals  will  seize  with  their  arms  a  light  boat 
and  overthrow  it  if  the  tentaculaB  are  not  cut  away 
with  a  hatchet.  The  French  corvette  Alecion 
encountered  a  gigantic  calmar  in  the  waters  of 
Teneriffe.  The  animal  was  secured  by  means  of  a 
harpoon  and  a  rope,  but  the  head  with  its  tentacles 
dropped  into  the  sea  while  it  was  being  drawn  on 
board,  owing  to  the  rope  cutting  through  the  soft 
flesh  of  the  creature. 

Marvels  have  been  recorded  even  of  the  teeth,  the 
skin,  and  the  spines  of  certain  species  of  fish.  The 
hooked  spines  of  the  ray  have  almost  invariably 
inspired  terror.  According  to  iElian  and  Pliny,  the 
wounds  made  by  the  sting  of  the  ray  are  incurable. 
The  former  relates  that  a  thief  who  was  making  off 
with  one  of  these  fish  was  wounded  by  its  s}>ines, 
and  died  immediately.  In  our  day  fishermen  have 
no  fear  of  it  at  all.  The  Japanese  consider  that  the 
best  possible  remedy  for  the  bite  of  serpents  is  to  rub 
the  place  with  the  spine  of  this  species  of  ray. 
Many  of  the  Japanese  carry  it  about  with  them  for 
the  purpose,  but,  strictly  speaking,  to  possess  this 
virtue  it  must  have  been  cut  from  the  living  fish 
and  applied  fresh  to  the  wound. 

The  negroes  believe  that  the  sting  Off  the  ray  is 
venomous,    but  thev  have  no  more  reason  for  this 


22  J  THE  BOTTOM  OF  THE  SEA. 

idea  than  the  Japanese  havo  for  their  notion  that 
it  serves  as  an  antidote  to  the  bite  of  serpents. 

Side  by  side  with  the  legends,  often  of  terrible 
import,  to  which  the  sea  and  its  inhabitants  have 
given  birth,  we  meet  with  others  of  a  ludicrous 
character.  Such  is  the  belief,  which  prevails  in 
the  North  of  Europe,  that  the  Anatifera  concha 
engenders  the  barnacle-goose.  The  barnacle,  as  all 
the  world  knows,  attaches  itself  to  rocks,  the  shells 
of  oysters,  and  other  testacea — to  any  solid  body 
floating  in  the  w^ater,  especially  to  the  hulls  of 
ships,  and  to  submarine  telegraphic  cables. 

The  protecting  envelope  of  this  animal  is  com- 
posed of  five  distinct  parts.  Through  two  opposite 
openings  the  antei  ..a?  or  tentacles  pass  out ;  they 
are  very  supple,  and  covered  with  filaments;  from 
another  part  protrudes  the  foot,  which  is  analogous, 
in  its  external  aspect,  to  the  branch  of  a  polypier. 
By  this  the  creature  fixes  itself  to  solid  bodies.  In 
the  midst  of  the  tentacles  is  a  kind  of  trunk,  in 
which  is  a  thin  tongue,  rolled  into  a  spiral  form,  and 
of  a  deep  colour.  The  trunk  or  trumpet-like 
process  is  transparent,  and  formed  of  a  series  of 
I'ings,  diminishing  in  diameter  from  the  base  to  the 
other  extremity.  The  tentacles  serve  as  a  kind  ol 
net  for  seizing  prey. 

When  the   barnacle  is  taken  from  the  water,  it 


f^E  BARNACLE'GOOSK.  221 

Quickly  dries  up,  and  to  such  a  degree  that,  after 
some  days,  it  is  very  difficult  to  find  among  the 
shells  the  remains  of  the  slirivelled  animal.  This 
lias  probably  given  rise  to  the  belief  in  the  marine 
origin  of  the  wild  duck.  The  canard  rising  from 
the  water  has  broken  its  shell,  and  left  nothing  but 
its  debris  on  the  shore.  Experience  and  reasoning 
are  powerless  in  face  of  this  prejudice.  If  the  rustics 
of  the  North  cannot  say  they  have  seen  the  canard 
leave  the  shell,  the  only  reason  is,  they  would 
answer,  that  it  is  hatched  during  the  night. 

Fabulous  legends  of  this  kind  have  hidden  the 
true  facts  in  a  surrounding  of  incredible  circum- 
stances, owing  to  the  strong  inclination  for  the 
marvellous  which  has  characterised  young  nations 
and  oriental  races.  The  sea  was,  in  olden  times, 
peopled  by  sirens  who  played  a  great  part  in  naviga- 
tion. Unlucky  was  it  for  the  voyager  who  had  too 
great  a  liking  for  art  and  beauty  !  Charmed  by  the 
perfidious  but  sweet  songs  of  the  siren,  he  became 
the  sport  of  fantastic  illusions ;  he  saw  imaginary 
coasts,  and  was  wrecked  on  invisible  rocks.  The 
siren  is  a  falnilous  being.  But  harmonious  sounds 
float  over  the  ocean,  though  perhaps  they  are  only 
those  made  by  the  sobbing  of  the  waves,  by  the 
suash  of  the  water  against  tlie  ship's  sides,  or  against 
tbe  bulk  of  some  great  fish. 


222  THE  BOTTOM  OF  THE  SEA. 

Without  reflection,  it  ini^;lit  appear  that  no  other 
sounds  than  such  as  these  contribute  to  the  o<eanie 
concert.  Fish  do  not  seem  to  possess  any  vocal 
organ,  and  if  their  throats  were  better  adapted  for 
the  emission  of  sound,  it  is  doubtful  if  we  could 
hear  their  songs.  Let  us  remember  that  sound 
results  from  the  vibration  of  some  elastic,  gaseous, 
liquid,  or  solid  body — that  sound  travels  more 
rapidly  in  water  than  in  air.  Considering  that  the 
celebrated  physicist  Cagniard-Latour  has  constructed 
a  little  apparatus,  by  the  aid  of  which  sounds  are  pro- 
duced at  will,  in  the  air  or  in  the  water,  and  which 
for  that  reason  he  calls  the  siren,  we  need  not  be 
astonislied  to  learn  that  many  fish  emit  sounds,  and 
that  in  some  instances  these  sounds  assume  the 
character  of  true  singing. 

Without  SDcaking  particularly  of  the  coincoin, 
whose  grunting  xjas  oeen  compared  to  the  cry  of  a 
wild  goose;  of  the  vieille^  which  utters  a  plaintive 
cry  when  it  is  seized ;  or  of  the  tunny,  which  wails 
like  an  infant  when  taken  from  the  water — let  us 
listen  for  a  moment  to  an  account  of  a  discovery  not 
many  years  ago  in  America.  The  narrator,  Mons. 
0.  de  Thoron,  was  walking  one  day  on  the  shore  of 
a  bay  situated  to  the  north  of  the  province  of  Es- 
meraldas,  in  South  America.  All  at  once,  when  the 
sun  was    setting,    he   heard    with  astonishment    an 


SonNDS  miAHD  AT  SEA.  22fl 

indefinable  sound,  very  sonorous  and  long  sustained; 
In  that  country,  where  the  insect  race  is  often  very 
troublesome,  he  thought  at  first  that  the  sound 
proceeded  from  insects  of  unusual  dimensions.  Failing 
to  discover  anything  of  the  kind  in  the  air,  or  on  the 
sea,  he  questioned  a  man  who  was  rowing  by,  and 
was  informed  that  the  sound  proceeded  from  a  fish, 
called  by  some  the  siren,  by  others  the  musician. 
M.  de  Thoron,  desirous  that  no  other  sound  should 
interrupt  his  enjoyment  of  this  phenomenon,  re- 
quested the  boatman  to  rest  on  his  oars.  All  around 
a  multitude  of  sounds  rose  from  the  sea,  forming  the 
most  singular  concert  it  is  possible  to  imagine ;  the 
undertone  of  a  church  organ  heard  at  a  considerable 
distance  might  be  said  to  resemble  it.  The  concert 
commenced  at  sunset,  and  continued  all  through  the 
night.  The  presence  of  auditors,  M.  de  Thoron  ob- 
serves, did  not  seem  in  the  least  to  intimidate  this 
new  species  of  choristers. 

They  build,  they  feast,  they  make  love,  they  steal ; 
they  live  in  captivity,  in  freedom,  or  are  enslaved  in 
the  ocean.  As  Fredol  says,  "  There  is  joy  in  its  waves, 
there  is  happiness  on  its  shores,  there  is  a  pervading 
bliss  throughout  all !"  Animal  life  displayed  in  the 
most  opposed  forms,  the  most  grotesque  organisa- 
tions, appears  in  greater  beauty  than  on  the  withered 
earth.     Tribes  of  living  creatures  rejoice  incessantly 


2'i4  mi^  BOTTOM  OP  THE  ^M, 

ill  the  most  marvellous  variations  of  light  and  shade, 
in  the  most  faiiylike  illuminations,  changing  and 
reversing  at  every  instant.  They  almost  talk,  they 
murmur  their  complaints,  they  sing,  they  get  up 
concerts  of  which  we  can  form  but  a  feeble  idea. 
What  tlien  is  wanting  to  the  completeness  of  life  in 
the  Ocean  ?— Only  Man. 

14.  Algae — The  mi  trodden  Forests  and  Prairies  of  tlie.  Ocean — 
Animal  Life  more  abundant  than  Vegetable  Life — Sea  Plants 
less  widely  distributed  than  Marine  Animals — Influence  o{ 
liight— Collection  of  Seaweed  on  the  Coasts — Assistance 
afforded  by  the  Tide. 

Marine  vegetable  life  is  very  far  from  equalling  in 
richness  the  animal  life  of  the  Ocean.  The  marine 
flora  is  limited  almost  entirely  to  one  class  of  plants — 
namely,  the  algge  tribe.  These  plants  assume  the 
most  strange  and  grotesque  forms  imaginable.  The 
number  of  species  seems  almost  unlimited.  The 
learned  Linnseus  counted  only  fifty,  but  at  the 
present  time  at  least  2000  are  known. 

As  we  have  remarked  in  an  earlier  chapter,  the 
marine  flora  is  developed  to  the  greatest  extent  in 
the  temperate  zones.  Its  extent  and  variety  may 
be  appreciated  from  the  fact,  that  in  English  waters, 
105  genera  and  370  species  of  algae  may  be  counted. 
The  richness  and  variety  of  this  class  of  plants 
diminish  gradually  as  we  recede  from  the  temperate 


EXTENt^ION  OF  LIFE  IN  THE  OCEAN.  225 

zones  towards  the  equator  or  the  poles.  **  It  is,  more- 
over, remarkable  that  the  law  under  whicli  tlie 
animal  kingdom,  which  more  readily  ada^its  itself  to 
surrounding  circumstances,  becomes  more  extensively 
developed  than  the  vegetable  kingdom,  applies  to 
the  ocean  as  well  as  to  the  land.  Thus  the  polar 
seas  abound  in  whales,  seals,  fish,  and  aquatic  birds, 
and  are  populated  by  an  infinite  multitude  of  inferior 
animals,  when  all  vegetation  has  disappeared  irom 
this  region  of  ice  and  cold.  This  law  is  also  found 
to  a})ply  as  we  descend  deeper  into  the  ocean,  ibr  in 
so  doing  we  discover  that  vegetable  life  disappears 
much  sooner  than  animal  life:  indeed,  in  abysses 
where  hardly  a  ray  of  light  can  penetrate,  soundings 
still  demonstrate  the  presence  of  living  infusoria3." 

We  know  what  life  does,  although  we  know  not 
what  ehe  is.  There  is  no  region  of  natural  phe- 
nomena to  which  this  remark  applies  more  forcibly 
than  to  the  ocean.  We  there  see  animals  blooming, 
so  to  speak,  in  the  most  brilliant  and  varied  colours, 
like  flowers,  and  flowers  almost  without  colour. 

On  the  other  hand,  the  animals  lose  their  power  of 
motion,  and  become  more  allied  to  the  algae  them- 
selves. Modern  investigations  show  that,  during  tlie 
first  part  of  their  existence,  vegetable  cells  have  the 
motions  characteristic  of  animal  life,  so  that  the 
algae   might  almost  be  considered  as  varieties  of 

Q 


226  THE  BOTTOM  OF  THE  SEA. 

polypier,  linking  together  the  two  kingdoms  of 
nature.  But  the  algae  do  not  petrify  like  the  polyp, 
to  whose  labours  we  owe  the  existence  of  the  coral 
reefs  of  the  Pacific ;  they  remain  soft  and  flexible,  at 
the  same  time  establishing  immense  colonies  of  their 
kind. 

Wliat  striking  objects,  what  prodigies,  do  we  find 
in  each  step  of  our  submarine  investigations !  Is  it 
matter  of  astonishment  that  in  the  presence  of  these 
marvels  man's  mind  should  have  invented  that 
fairy  mythology,  the  memory  of  which  has  been 
partly  perpetuated  by  the  legends  of  the  middle 
ages? 

Marine  plants  are  sometimes  microscopical.  Their 
floating  millions  sometimes  colour  the  sea ;  among 
others,  the  Ked  Sea  owes  its  name  to  such  circum- 
stances. At  certain  seasons  of  the  year,  this  sea 
swarms  with  filamentous  confervae  of  a  beautiful 
purple  colour.  The  beautiful  tint  which  has  from  a 
remote  period  given  thissea  the  name  of  Eryth  rsean, 
is  due  to  the  infinite  numbers  of  the  marine  con- 
fervae. In  other  cases  marine  plants  attain  gigantic 
dimensions.  The  Wellingtonia  gigantea  is  no  dwarf 
in  size,  but  what  comparison  can  there  be  between  it 
and  the  Varec  porte-j)oire  of  Terra  del  Fuego,  which 
grows  to  a  height  of  1000  feet ! 

Marine  plants  have  no  need  of  earth.     They  grow 


THEES  WITHOUT  BOOTS.  Z27 

anywhere,  as  their  nourishment  is  not  obtained  from 
the  soil,  but  from  the  sea  itself.  For  the  same 
reason  they  have  no  root ;  indeed,  the  species  which 
float  have  not  even  the  semblance  of  roots,  while 
those  which  remain  (stationary  are  attached  by  a 
species  of  sucker  more  or  less  lobed  or  divided.  The 
earth  goes  for  nothing  in  their  development,  because 
their  origin  is  always  exterior.  Their  whole  growth 
is  in  the  water,  which  supplies  all  they  need,  and  to 
which  all  ultimately  return.  Land  vegetation  would 
not  find  sufficient  subsistence  in  the  atmosphere;  it 
requires  a  soil,  and  trunk,  and  branches.  The  alga 
is  supporte'l  by  the  water  on  which  it  feeds ;  it  is  held 
down  by  the  rock  or  earth  to  which  it  is  attached ;  if 
it  becomes  detached,  instead  of  falling  like  a  tree,  it 
rises  and  floats  on  the  surface  of  the  water. 

As  terrestrial  plants  yield  a  resting-place  for  the 
eggs  of  birds  and  insects,  so  do  seaweeds  for  marine 
animals ;  but,  instead  of  suppoi  ting  them,  it  jjrevents 
them  from  rising  to  the  surface,  and  also  shelters 
them  from  the  voracity  of  the  monsters  of  the  deep. 

As  the  insect  tribes  establish  their  republics  in  the 
trees  of  our  forests,  so  the  sponges  attach  themselves 
to  the  light  algae,  and  the  polypi  take  them  for  their 
fragile  base.  Even  the  sea-worm,  like  the  terrestrial 
serpent,  winds  its  encircling  length  around  the  steuis, 
the  better  to  seize  its  prey. 


228  thjj:  botwm  of  the  sea. 

How  strange  a  tree  would  look  which,  torn  up  by  the 
tempest,  should  rise  through  the  atmosphere  and  float 
above  the  clouds  !  Such  phenomena  occur  continue lly 
in  the  ocean.  The  marine  currents  detach  plants  of 
all  kinds  from  the  bottom  of  the  ocean.  They  collect 
in  parts  of  the  ocean  where  the  currents  are  weaker. 
There  they  form  immense  floating  islands,  which 
sometimes  hinder  the  progress  of  ships. 

Light  is  as  necessary  for  marine  plants  as  for 
terrestrial  ones,  and  this  prevents  them  from  living 
at  a  great  depth  ;  still  they  grow  many  hundred  feet 
below  the  surface,  where  light  penetrates  but  feebly. 
Shells  are  distinctly  visible  in  certain  parts  of  the 
Arctic  Ocean  at  a  depth  of  460  feet ;  at  a  depth  of 
940  feet  the  light  is  still  of  sufficient  intensity  to 
permit  the  objtcts  to  be  seen  dimly.  The  bottom 
of  tlie  sea  is  equally  visible  at  the  same  depth  in 
the  Antilles,  but  the  objects  are  not  distinct.  Abso- 
lute darkness  prevails  at  a  depth  of  1000  feet.  The 
rays  of  the  moon  penetrate  only  to  a  deptii  of  about 
40  feet. 

It  is,  therefore,  within  a  limit  of  1000  feet  in  depth, 
or  about  one-tenth  of  the  average  depth  of  the  seas, 
that  marine  plants  vegetate,  forming  a  belt  around 
our  continents  and  islands,  or  crowning  the  summits 
of  submerged  mountains. 

H^s  light  any  influence  on  the  colour  of  vegetation 


DISTRIBUTION  OF  THE  ALG/E.  229 

iu  the  sea  ?  Modem  botanists  have  proved,  experi- 
mentally, that  plants  ai-e  very  sensible  to  the  action 
of  ligbt,  and  it  has  been  found  that  marine  plants 
are  of  different  colours,  according  to  the  depth  at 
which  they  grow. 

They  have  been  divided,  according  to  their  pre- 
vailing tint,  into  three  main  sections :  the  brown  or 
black  (mdanosj)ermea),  the  green  {chloros^pertnea),  and 
the  red  (rhodosperniea).  The  green  live  only  near 
the  surface ;  they  often  float,  and  are  found  in  large 
quantities  in  the  grassy  seas.  The  red  are  found  at 
small  depths  on  rocks  near  the  coasts.  The  brown, 
which  are  much  more  numerous,  grow  at  greater 
depths.  They  constitute  the  greater  part  of  the 
submarine  forests. 

Although  the  alga3  occupy,  relatively,  but  a  small 
portion  of  the  earth's  surface,  being  distributed  in 
what  may  be  called  oceanic  belts,  their  number  is 
immense.  Wherever  the  physical  conditions  are 
favourable  to  their  development,  they  fill  the  sea 
with  their  impenetrable  masses.  This  abimdant 
vegetation  is  utilised  by  man,  whom  the  sea  itself 
aids  in  collecting  them.  Wind-storms  sometimes 
produce  terrible  effects,  but  oceanic  storms  far 
exceed  them  in  destructive  force.  If  the  first  over- 
throw enormous  trees  or  immense  edifices,  the  latter 
easily  tear  whole  forests  of  marine  plants  ftom  theii* 


2B0  THE  BOTTOM  OF  THE  SEA. 

feeble  hold  of  the  soil  or  rocKs.  This  madness  of 
the  ocean  is  man's  gain.  On  the  various  coasts,  and 
especially  in  the  bays  of  the  ocean,  he  collects  the 
seaweed  which  is  thrown  ashore  by  each  tempest, 
and  even  by  every  tide,  in  quantities  which  may  be 
called  incalculable,  and  yet  the  supply  seems  never 
to  diminish.  There  are  bays  in  w  hich  30,000  people 
are  sometimes  occupied  in  gathering  this  spoil. 

Seaw  eed  makes  very  bad  fuel,  but  it  is  occasionally 
used  for  firing.  Its  most  hnportant  use  is  as  manure, 
or  as  the  raw  material  of  soda,  which  is  extracted 
from  its  ashes.  A  still  more  curious  application  of 
it  is  made  by  the  Dutch,  who  use  seaweed  in  con- 
structing the  dams  which  preserve  their  lands  from 
the  inroads  of  the  sea:  thus  the  ocean  itself  fur- 
nishes the  materials  which  are  to  be  opposed  to  it 
as  an  obstacle.  Alas!  we  know  too  well  that  the 
courageous  efforts  of  the  inhabitants  of  the  country 
must  at  last  fail,  and  that  the  sea  will  again  assert 
its  dominion  over  the  earth  and  the  ephemeral  works 
of  man ! 


MAN  AND  HIS  WORK  AT  THE  BOTTOM   OP  THE  SEA. 


I.  The  Empire  of  the  Seas  denied  to  Man — Numerous  attempts  at 
Submarine  Exploration — T  )isturbance  of  j)resent  social  conditions 
which  would  ensue  from  the  possibility  of  travelling  beneath  the 
Surface  of  the  Water — The  Sea  the  best  tie  between  Nations. 

Air  is  necessary  to  the  life  of  man  ;  his  organisa- 
tion forbids  a  too  protracted  stay  beneath  the  surface 
of  the  water.  If  he  dives  he  is  soon  compelled  to 
return  to  the  surface.  He  is,  therefore,  unable  to 
acquire  any  extensive  acquaintance  with  the  sub- 
merged part  of  the  earth,  for  no  sooner  does  the 
depth  exceed  a  few  feet  than  some  special  apparatus 
becomes  requisite.  The  explorations  which  have 
been  made,  however,  besides  their  theoretical  im- 
portance, have  resulted  in  great  commercial  gain. 

What  enormous  wealth  has  been  engulfed  in  the 
sea  since  man  first  dared  its  dangers,  and  entrusted 
his  treasures  to  its  fatal  grasp !  Each  year  a  further 
tribute  is  levied  by  the  moving  torrent  of  waters, 
whicli  yields  up,  here  andthere,an  insignificant  portion 
of  its  spoil,  but  jealously  guards  the  more  precious 


232  THE  BO  I  TOM  OF  THE  SEA. 

treasures  in  its  secret  bosom.  How  could  the  faintest 
hope  exist  that  the  mighty  ships  laden  with  rich 
merchandise,  which  have  sunk  beneath  the  surface, 
could  ever  again  be  recovered  ?  What  man  so  daring 
as  to  attempt  their  extraction,  piece  by  piece,  from 
the  ocean  which  hides  them  with  such  jealous  care  ? 

Every  such  enterprise  was  for  long  considered 
merely  chimerical.  Even  now,  any  attempt  of  the 
kind  is,  in  most  cases,  impracticable ;  and  in  those 
rare  instances  where  some  hope  of  success  may  fairly 
be  indulgod,  it  is  only  by  great  sacrifices,  and  by  the 
exercise  of  much  ingenuity,  that  our  expectations  are 
adequately  realised. 

In  presence  of  the  vast  ness  of  the  sea,  man  is  in- 
voluntarily impressed  with  mingled  respect  and 
terror.  He  may  sail  about  on  its  surface  boldly 
enough,  but  he  penetrates  its  depths  with  hesitation. 
In  his  pursuit  of  a  marine  monster,  he  liarasses  it  so 
long  as  it  imprudently  remains  near  the  surface  of 
its  vast  empire.  No  sooner,  however,  does  the 
monster  feel  the  power  of  his  enemy,  and  the  danger 
of  remaining  within  his  reach,  than  he  sinks,  though 
only  a  few  yards,  down  into  the  abyss  of  waters,  and 
man's  power  of  pursuit  immediately  ceases. 

If  nature  had  gone  so  far  as  to  endow  man  with  a 
large  reservoir,  where,  like  the  whale  and  other  sea- 
monstersj  he  could  store  up  a  sufficient  Yolurae  of 


AUDAdry  OP  kXPLOliEUS.  2:^3 

air,  and  carry  it  with  liim  to  the  farthermost  depths 
of  the  ocean,  what  service  conld  he  extract  from  so 
marvellous  a  provision,  if  his  eyes,  constructed  so  as 
to  give  him  the  power  of  vision  in  a  limpid  and 
dazzlingly  luminous  atmosphere,  made  him  conscious 
only  of  darkness,  and  left  him  a  defenceless  prey  to 
the  voracity  of  the  monsters  of  the  deep  ? 

But  man  is  ambitious  to  assert  his  sovereign  right 
over  the  whole  globe  ;  universal  nature  is  his  inheri- 
tance, and  he  studies  her  every  phase  and  all  her 
changing  humours  with  patience.  In  his  thirst  for 
knowledge  he  fearlessly  grapples  with,  and  seldom 
fails  to  overcome,  whatever  obstacle  may  be  thrown 
in  his  path.  With  a  sublime  audacity  he  would 
penetrate  and  master,  in  every  direction,  an  empire 
the  limits  of  which  appear  to  him  to  be  too  narrow. 
He  is  not  satisfied  to  run  with  lightning-speed  over 
the  surface  of  the  earth ;  he  would  also  cleave  the 
air  like  a  bird,  and  dispute  their  darkest  and  dreariest 
retreats  with  the  inhabitants  of  the  seas.  As  if 
conscious  of  her  irresistible  attractions,  the  Ocean 
allows  him  occasional  glimpses  of  her  treasured 
charms,  and,  at  the  same  time,  one  might  almost 
say  that  she  defies  him  to  deprive  her  of  any  portion 
of  them.  Corals,  sponges,  and  pearls  have  to  be 
8nat(*hed  from  her  depths.  The  magnificent  pur[)l » 
of  the  ancients — sepia,  mother-of-prarl,  ambergris — 


234  THE  BOTTOM  OF  THE  SKA. 

are  but  a  few  of  the  valuable  substances  which  are 
well  known  to  be  of  oceanic  origin. 

Ambition  and  the  love  of  gold  are  an  almost  uni- 
versal motive  power.  Poverty  and  fear  often  supply 
their  place.  The  first  attempts  at  circumnavigation 
were  made  by  daring  sailors  imbued  with  a  desire  to 
make  a  rapid  fortune.  Sponges  and  pearls  were  long 
procured  exclusively  by  the  labour  of  slaves.  In 
many  parts  of  the  world  the  old  fashion  is  still  fol- 
lower], insofar  that  diving  is  the  only  means  employed 
to  obtain  those  treasures  of  the  deep.  The  process  is 
of  the  most  primitive  kind.  On  reaching  the  scene 
of  his  labours,  the  adventurous  diver  detaches  the 
sponge  from  the  rocks  to  which  it  is  fastened  ;  nets 
are  suspended  from  boats  and  sunk  within  reach  of 
the  workmen,  who  fill  them  with  their  spoil,  and, 
on  a  signal  being  given,  the  well-laden  nets  are  drawn 
up  by  a  cord. 

Edible  oysters  inhabit  the  European  and  Indian 
seas;  they  are  very  abundant  on  the  French  and 
English  coasts.  Oyster-fishing  is  carried  on  by  means 
of  a  net  furnished  with  a  scraper,  which  is  dragged 
over  the  rocks  to  which  the  oysters  are  fixed.  The 
oysters  detached  from  the  bottom  are  accumulated  in 
the  net,  together  with  any  other  animals  which  ac- 
company them. 

As  Goldsmith  relates,  the  unfortunates  condemned 


DIVERS  AND  TnFJTt  PERJLS.  2^5 

to  the  painful  and  laborious  occupation  to  which 
we  have  referred  on  the  coasts  of  Persia,  are  either 
the  negroes  or  the  poorest  of  the  inhabitants.  Divers 
not  only  run  the  risk  of  drowning,  and  of  being  de- 
voured by  sharks,  but  they  are  also  in  danger  of 
being  suffocated  in  consequence  of  having  to  hold 
their  breath  for  a  protracted  time ;  and  if  no  worse 
effects  ensue,  this  condition  often  results  in  blood- 
spitting.  The  most  robust  and  liealthy  young  men 
are  chosen  for  this  tra^Je,  but  they  can  seldom  con- 
tinue in  it  for  more  than  five  or  six  years.  Their 
fibres  stiffen,  the  pupils  of  their  eyes  become  red, 
and  they  often  die  of  consumption.  .  .  .  They  deposit 
tlie  pearls,  or  rather  the  oysters  which  contain  them, 
in  boats  28  feet  long,  of  which  there  are  often  800 
or  400  at  sea  at  one  time.  Each  of  these  boats  has 
seven  or  eight  stones,  w^hich  serve  it  as  anchors,  and 
on  board  are  from  five  to  eight  men,  who  dive  by 
turns.  They  are  all  naked,  hut  have  a  net  sus- 
pended from  their  necks,  into  vhich  they  throw  the 
oysters;  their  hands  are  gloved,  to  preserve  them 
from  the  wounds  wliich  they  might  otherwise  get  in 
detaching  the  shells  from  the  rocks.  'I'hey  descend 
with  the  help  of  a  cord,  to  whicli  is  attached  a  weight 
of  about  50  pounds.  They  place  their  feet  in  a  kind 
of  stirrup ;  w  ith  the  left  hand  they  hold  the  cord, 
and  with  the  right  they  close  the  nostrils,  to  prevent 


23e  Tmi  noTToM  of  Tnn  sp:a. 

the  exit  of  tlie  air,  of  which  they  have  taken  a  deep 
breath  previous  to  tlieir  descent.  Having  reached 
the  bottom,  they  commence  operations  by  giving  the 
signal  to  those  who  remain  in  the  boat  that  they 
may  raise  the  stone,  after  which  they  set  to  work 
collecting  the  shells,  with  which  they  fill  their  nets 
as  speedily  as  possible ;  they  then  make  another 
signal,  upon  which  the  net  is  raised,  and  immediately 
afterwards  tliey  themselves  rise  to  breathe.  All  the 
shells  are  carried  to  the  shore,  where  they  are  piled 
in  heaps  until  the  fishiug-season,  which  lasts  during 
November  and  December,  is  at  an  end. 

The  holothuria,  or  trejpang,  much  sought  after  in 
Asia,  is  gathered  by  divers,  or  harpooned  on  the 
bodies  to  which  it  attaclies  itself.  The  harpoon  is 
fixed  to  the  extremity  of  a  series  of  long  bamboos 
fitting  one  within  another.  Leaning  over  the  bow  of 
his  boat,  the  fisher  gazes  into  the  depths  of  the  sea ; 
the  most  perfect  calm  is  indispensable,  and  it  is  as- 
serted that  in  such  case  he  can  see,  at  a  depth  of 
100  feet,  the  animal  attached  to  the  rocks  or  coral 
banks ;  the  harpoon  descends  as  gentb^  as  possible 
until  it  reaches  the  animal,  when  it  strikes  it  sud- 
denly, and  rarely  in  vain. 

In  the  greatest  number  of  instances  the  diver  de- 
scends as  far  as  his  sight  will  permit  him,  but  this 
.<  to  a  si i ght  depth  only     Moflern  apparatus  facilitates 


3 


f 
s 

I 


SUBMARINE  VESSELS.  239 

his  expeditions,  but  it  has  not  much  extendea  tneir 
radius.  In  fact,  the  pressure  supporterl  by  tne  in- 
trepid explorer  augments;  by  one  atmosphere  when 
he  has  reached  a  depth  of  32  feet ;  it  soon  becomes 
80  great  as  to  involve  conditions  in  which  it  would  be 
impossible  to  live.  Asphyxia,  ravenous  monsters,  and 
darkness,  are  not  therefore  the  only  obstacles  which 
man  has  to  encounter  in  his  submarine  ex[)lorations. 
He  cannot  descend  into  the  immense  oceanic  valleys 
as  he  faces  the  cold  and  rarefaction  of  the  air  on  the 
high  mountains  of  the  terrestrial  surface.  Beyond 
the  region  of  the  monsters  he  must  enter  the  realms 
of  darkness,  and,  should  he  go  further  still,  encounter 
sure  destruction. 

Who  can  form  an  idea  of  the  immense  chanofes 
which  would  result  if  men  were  able  to  travel  freely 
under  the  surface  of  the  waters?  Where  would 
be  the  natural  frontiers  which  politicians  so  much 
desiderate  ?  Man  darting  through  the  air  like  a  bird ; 
locomotives  competing  with  the  eagle  in  point  of 
speed,  and  losing  themselves  in  the  midst  of  the 
clouds;  powerful  machines  plunging  beneath  the 
oceanic  tempests,  and  scattering  in  terriHed  hosts 
the  multitudinous  inhabitants  of  the  sea!  Who 
would  dare  to  entertain  for  one  moment  dreams  or 
aspirations  of  so  chimerical  a  nature  ?  Great  minds 
have  nevertheless  devoted  their  labours  and  thoughts 


240  TEi:  BOTTOM  OF  THE  SEA. 

to  .«siich  objects,  and  we  shall  presently  see  how  they 
iiave  partially  resolved  the  question  in  respect  to  the 
(Jcean.  Sailors  of  a  new  order  may  now  be  shipped 
for  submarine  expeditions;  the  adventurer  can 
already  carry  with  him  a  provision  of  air,  light,  and 
food;  Ite  can  sink  or  rise  at  will, or  maintain  himself 
at  any  particular  depth,  like  a  s[)irit  of  the  deep ;  he 
can  suddenly  make  his  presence  felt  in  the  midst  of  a 
fleet,  or  on  a  hostile  coast,  before  the  astounded  enemy 
has  time  to  prepare  for  defence ;  he  can  discharge  his 
powerful  batteries  and  engulf  himself  in  his  adopted 
element,  like  a  true  marine  monster,  while  they  seek 
in  vain  for  the  cause  of  the  disaster  with  which  they 
are  suddenly  smitten. 

If  a  few  steps  have  been  made  towards  the  realisa- 
tion of  such  marvels,  how  many  more  still  remain 
to  be  accomplished  !  It  will  perhaps  never  be  man's 
lot  to  tread  the  hitherto  unfathomable  abysses  of  the 
sea ;  the  hum  of  civilisation  will  never  disturb  the 
profound  peace  which  the  monsters  of  the  deep  are 
themselves  bound  to  respect.  At  any  rate,  there  must 
be  patient  waiting  through  a  long  series  of  ages  for 
this  result,  and  we  must  leave  to  our  descendants  the 
care  of  adding  another  chapter  to  the  history  of  the 
earth.  They  may  perhaps  see  cultivated  lands,  forests, 
and  mountains,  where  the  present  level  of  the  sea  per- 
mits only  a  wild  waste  of  waters ;  or  perliaps  they  may, 


THE  SEA  AND  ITS  SFOlLS.  241 

in  digging  their  roads,  canals,  and  tunnels,  study  the 
deposits  now  in  course  of  actual  formation,  whilst  coral 
reefs,  sponges,  and  oyster-banks  will  cover  the  edifices 
of  which  we  are  now  so  proud. 

Without  descending  to  any  great  depth,  we  may 
see  even  near  tlie  surface  and  the  coast,  in  the  midst 
of  reefs  which  seem  to  permit  man  to  penetrate  the 
oceanic  waste  but  to  forbid  his  return,  submarine  life 
conspire  with  the  waters  to  bury  out  of  sight  the 
evidences  of  the  destruction  they  have  wrought- 
The  nations  would  be  rich  if  the  sea  did  not  levy  a 
heavy  tribute  upon  them.  But  the  sea  only  corrodes 
and  wastes  the  spoil  it  seizes ;  the  abundance  of 
oceanic  life  engulfs  it  a  second  time.  Molluscs,  bar' 
nacles,  and  seaweed  veiy  readily  attach  themselves 
to  bodies  plunged  into  the  sea.  Ships  which  make 
long  voyages  sometimes  become  loaded  with  so  enor- 
mous a  cargo  of  shells  and  barnacles,  tliat  they  re- 
semble floating  aquarii,  and  lose  much  of  their  speed. 
The  work  of  the  sea  is  incessant.  Every  hour,  every 
minute,  adds  to  the  thickness  of  the  covering  with 
which  she  conceals  her  thefts ;  and  so  long  as  the 
methods  of  search  remain  as  imperfect  as  they  are  at 
present,  we  must  be  content  if  we  recover  occasion- 
ally such  fragments  only  as  this  fascinating  monster 
is  willing  to  render  up. 

We  are  prevented  by  a  variety  of  causes  from 

R 


242  THE  BOTTOM  OF  THE  SEA. 

exploring  by  far  the  larger  portion  of  the  earth's  crust. 
Nature  has  been  jealously  careful  to  remove  it  from 
our  sight,  to  preserve  it  from  our  unappeasable  curi- 
osity. Should  we  not  congratulate  ourselves  on  this 
fact  ?  And  does  not  this  water,  which  hides  so  many 
marvels,  serve  now,  and  has  it  not  always  served,  to 
human  need,  as  one  of  our  most  powerful  auxiliaries  ? 
It  is  water  which  most  facilitates  the  relations  that 
are  established  between  the  inhabitants  of  different 
countries,  which  invites  to  exchanges  and  transactions 
of  all  kinds,  and  is  in  fact  the  soul  of  commerce,  of 
which  civihsation  is  the  offspring. 
•  Though  flourishing  on  the  coasts,  civilisation  pe- 
netrates but  slowly  into  the  interior  of  continents. 
By  the  sea  it  is  speedily  transmitted  from  shore  to 
shore  of  neighbouring  islands,  and  so  on  to  the  re- 
motest. On  the  continent  it  spreads  slowly,  step 
by  step,  and  its  progress  is  almost  invariably  paral- 
lel with  the  course  of  rivers  and  streams.  Ee- 
move  the  water,  and  civilisation  would  disappear; 
the  desert  would  again  reign  supreme ;  one  waste  of 
sand  would  cover  everything  with  a  moveable  shroud, 
like  the  waves  of  the  sea,  but  even  more  terrible. 
How  many  have  paid  with  their  lives  for  the 
audacity  which  impelled  them  to  penetrate  the 
secrets  of  the  desert ! 

To  all  who  have  the  courage  to  confide  in  her.  the 


DIVING  APPARATUS.  243 

sea  provides  a  means  of  transport  at  once  agreeable 
and  convenient.  The  sea  supports  tlie  load,  the 
wind  propels  it,  and  man  directs  it  on  its  journey. 
From  this  easy  means  of  transport  results  a  great 
commercial  movement,  a  circulation  of  ideas  as  well 
as  products,  which  enlarges  the  iield  of  industrial 
genius,  encourages  useful  inventions,  promotes  that 
affability  and  those  humane  feelings  which  spring 
from  much  intercourse,  and,  in  a  word,  developes 
relations  between  one  people  and  another  which 
could  not  otherwise  be  established.  Further,  the 
discoveries  of  sailors,  the  voyages  to  distant  countries, 
to  very  different  climates  with  varied  productions, 
the  rapidity  of  exchange,  and  the  wellbeing  which 
results,  are  the  first  step  towards  that  universal 
union  which  is  the  end  and  aim  of  all  civilisation 
properly  understood. 


2.  Exploration  of  the  Bottom  of  the  Sea — Diving  Apparatus — In- 
vention of  MM.  Eouquayrol  and  Denayrouze  —  Submarin(i 
Electric  lUuminatiun — Salvage  of  objects  sunk  in  the  Sea — A 
Chest  of  Gold  recovered  under  peculiar  circumstances  in  the 
Port  of  Marseilles. 

The  exploration  of  the  bottom  of  the  sea  made  but 
little  progress  in  ancient  times,  or  in  the  middle 
ages.  During  many  centuiies  the  few  attempts  of 
which    we   hear    are    rather    of    a   legendary   than 


244  THE  BOTTOM  OF  THE  SEA. 

authentic  character.  We  can  scarcely  be  astonished 
at  this  when  we  picture  to  ourselves  the  profound 
ignorance  which  prevailed  relative  to  the  properties 
of  gases.  Aristotle,  for  example,  wishing  to  demon- 
strate the  weight  of  atmospheric  air,  weighed  an 
empty  bladder,  and  the  same  bladder  again  when 
filled  with  air,  and  found  no  difference  between  the 
two  results.  Hardly  three  centuries  ago,  the  fact  of 
water  rising  in  the  tube  of  a  pump  was  explained  by 
the  supposition  tliat  Nature  abhors  a  vacuum. 

It  is  hardly  a  century  since  the  celebrated  astro- 
nomer Halley,  commencing  the  experiments  in  sul)- 
marine  exploration  which  have  been  continued  to 
our  time,  descended  to  a  depth  of  50  feet  in  a 
diving-bell  which  he  had  constructed.  English 
engineers  utilised  this  invention  until  the  year  1830, 
in  building  the  immense  submarine  structures  with 
which  they  have  covered  the  English  coasts.  At 
this  time  another  apparatus,  more  convenient  and 
at  the  same  time  less  costly,  gradually  replaced  the 
diving-bell. 

The  object  of  the  diving  apparatus,  to  which  we 
are  now  referring,  is  to  give  to  each  individual  work- 
man the  utmost  possible  liberty  of  movement.  An 
impervious  habit,  made  of  cloth  and  metal,  allows 
him  a  certain  liberty  of  motion,  which  he  cannot 
possibly  have  when  enclosed  in  a  bell.     A  pipe  com- 


RECENT  INVENTIONS. 


245 


municating  with  the  interior  of  liis  clothing  supplies 
him  with  the  air  necessary  to  respiration.  This 
air  is  supplied  by  a  lift  and  force-pump^  placed  on 
the  bank  or  in  a  boat.     This  apparatus  is  of  French 


Attempts  of  a  diflferent  kind  were  made,  at  the  end 


Fig.  46. — Divei-s  dressed  in  the  Apparatus  invented  by  MM.   PiOuquayroI 
and  Denayrouze. 

of  the  last  century,  by  an  inhabitant  of  Breslau.  A 
diver  descended  into  tlie  water  carrying  his  supply 
of  air  in  a  reservoir,  into  which  large  quantities  of 


246  THE  BOTTOM  OF  THE  SEA. 

this  gas  had  been  compressed.  The  man  C£,rried  this 
reservoir  on  his  back,  and  it  communicated  with  his 
mouth  by  a  tube. 

Mhurr  also  made  attempts  to  improve  the  appa- 
ratus in  France,  but  without  superseding  the  original 
invention.  In  England  some  form  of  the  apparatus 
was  constantly  used,  and,  in  1830,  the  discovery  of 
caoutchouc  gave  a  great  impulse  to  this  industry, 
and  improvements  became  more  feasible,  at  the  same 
time  that  they  were  more  necessary  than  ever.  This 
was  the  state  of  affairs  when  two  Frenchmen — M. 
Rouquayrol,  a  mining  engineer,  and  M.  Denayrouze, 
a  naval  lieutenant — solved  this  difficult  problem. 
Their  apparatus  suffices  for  all  the  exigencies  of  sub- 
aqueous work.  Whether  the  man  be  naked,  or  covered 
with  impervious  clothing,  his  respiration  depends 
entirely  on  the  exercise  of  his  own  will,  and  on  the 
power  of  his  lungs. 

This  result  is  obtained  by  means  of  an  artificial 
lung!  or  supply-regfulatoTy  which  consists  of  a  reservoir 
made  of  steel  or  iron,  capable  of  resisting  very  great 
pressure,  and  surmounted  by  a  chamber  so  constructed 
as  to  regulate  the  afflux  of  air.  The  diver  carries 
this  apparatus  on  his  back.  A  respiratory  tube  issues 
from  this  chamber,  and  is  terminated  by  a  mouth- 
piece composed  of  a  piece  of  sheet-caoutchouc,  which 
is  lield  betw€)en  the  lips  an/i  the  teeth  of  the  diver. 


AN  ARTIFICIAL  LUNG.  247 

This  pipe  is  furnished  with  a  valve,  which  permits 
the  expulsion  of  air,  but  opposes  tiie  entrance  of 
water.  The  steel  reservoir  is  separated  from  the 
air-chamber  by  a  conical  valve  opening  from  the 
air-chamber  towards  the  reservoir  in  such  a  manner, 
as  to  open  only  by  the  influence  of  an  exterior 
pressure — the  pressure  of  the  air  in  the  reservoir 
tending  to  close  it. 

It  is  obvious  that  the  use  of  this  apparatus  renders 
the  regular  working  of  the  air-pump  unnecessary. 
The  air  which  it  transmits  to  the  diver  is  stored  up 
in  the  steel  reservoir.  From  this  store  the  diver 
can  supply  his  needs  without  fatigue  in  the  following 
manner. 

The  air-chamber  is  closed  by  a  moveable  lid,  to 
which  is  attached  the  tail  of  the  conical  valve.  The 
diameter  of  the  lid  is  somewhat  less  than  the  interior 
diameter  of  the  chamber,  and  it  is  covered  with  caout- 
chouc to  render  it  airtight.  It  yields  to  both 
interior  and  exterior  pressure — the  former  causing 
it  to  rise,  the  latter  to  fall. 

When  exterior  pressure  is  exerted  on  this  lid, 
the  valve  is  immediately  affected  through  the  in- 
termediary tail  or  rod ;  communication  between  the 
reservoir  and  the  air-chamber  is  opened,  and 
a  portion  of  the  compressed  air  flows  into  the 
chamber.     Should   the   latter  contain  an  excess  of 


248  THE  BOTTOM  OF  THE  SEA. 

SLIT,  the  pressure  of  it  against  the  moveable  lid  keeps 
the  valve  closed. 

The  entire  apparatus,  when  under  water,  works  as 
follows.  By  drawing  in  his  breath,  the  workman  re- 
moves a  certain  part  of  the  air  from  the  chamber ; 
exterior  pressure  is  then  immediately  exerted  on  the 
moveable  lid,  v/hich  falls,  and  through  the  intermediate 
rod  causes  the  valve  to  open.  Air  issues  from  the 
reservoir,  and  re-establishies  the  equilibrium  between 
the  interior  of  the  air-chamber  and  the  surrounding 
medium  ;  the  lid  rises,  and  the  conical  valve,  returning 
to  its  former  position,  again  intercepts  the  communi- 
cation between  the  reservoir  and  the  air-chamber, 
until  another  aspiration  brings  about  a  repetition  of 
these  phenomena.  When  the  workman  respires,  the 
valve,  which  we  have  already  mentioned  as  existing 
in  the  respiratory  tube,  permits  the  air  expelled  from 
the  lungs  to  escape  into  the  water. 

This  apparatus  works  automatically ;  whatever  be 
the  irregularity  in  the  working  of  the  air-pump,  its 
action  is  as  regular  as  that  of  the  steam-engine.  The 
workman  receives  exactly  the  quantity  of  air  necessary 
for  respiration  ;  this  air  reaches  him  at  a  pressure  equi- 
valent to  that  to  which  the  rest  of  his  body  is  submitted, 
and- he  is  able  to  breathe  without  attention  or  effort. 

MM.  Eouquayrol  and  Denayrouze,  not  content  with 
having  enabled  the  workman  to  breathe  independently 


SUPPLY  OF  AIR.  249 

of  the  action  of  the  pump,  have  considerdbly  improved 
the  latter  apparatus  by  constructing  pumps  in  such  a 
manner  that  the  leakage  decreases,  until,  as  the  pres- 
sure increases,  it  can  scarcely  be  appreciate  1. 

It  is  well  known  that  air  becomes  hot  simply  by 
being  strongly  compressed.  The  supply  of  air  in  the 
heated  state  is  injurious  to  the  divers.  The  pumps 
of  which  we  speak,  and  in  which  the  air  traverses  two 
layers  of  water  before  entering  the  steel  reservoir, 
remedy  this  inconvenience.  Moreover,  the  air,  in 
p6i8sing  from  the  steel  reservoir  into  the  air-chamber, 
from  whence  the  workman  is  supplied,  expands  again 
and  becomes  still  cooler.  Another  important  advan- 
tage connected  with  this  apparatus  is  that  the  expired 
air  rises  in  bubbles  to  the  surface.  So  long  as  the 
diver  breathes  regularly,  the  intervals  which  separate 
the  appearance  of  the  bubbles  are  sensibly  equal.  It' 
they  come  more  rapidly  or  more  slowly  than  usual,  it 
IS  a  sign  that  something  abnormal  is  going  on.  It 
they  cease  altogether,  the  diver  must  have  ceased 
breathing,  and  should  be  hauled  up  immediately. 

In  the  old  diving-dress  the  air  filled  the  space  be- 
twixt the  body  of  the  diver  and  his  impervious 
clothing,  the  expired  air  escaping  by  a  little  valve 
fitted  into  the  helmet.  But  the  excess  of  air  trans- 
mitted by  the  pump  also  escaped  by  this  valve.  Ir- 
regularity in   working   the   pump   would   therefore 


250  THE  BOTTOM  OF  THE  SEA. 

cause  irregularity  in  the  escape  of  the  bubbles,  and 
if  the  pumpers  continued  their  work  they  might,  quite 
unconsciously,  fur  a  long  time  continue  to  send  air  to 
a  corpse.  With  the  new  apparatus,  however,  the 
escaping  air  affords  constant  evidence  of  the  health 
of  the  diver.  The  moment  he  requires  help,  his  at- 
tendants are  on  the  qui  vive,  while  in  the  former  case 
they  could  know  nothing  of  his  condition.  This  ad- 
vantage in  the  new  apparatus  can  hardly  fail  to  en- 
courage the  most  timid. 

Further,  he  who  wears  the  old  apparatus  exposes 
his  life  much  more  than  he  who  uses  the  apparatus  of 
Rouquayrol  and  Denayrouze.  His  life,  or  at  least 
the  security  and  duration  of  his  labours,  depend  en- 
tirely on  the  strength  and  substance  of  his  clothino. 
In  the  new  system  the  caoutchouc  dress  serves  only 
to  protect  the  diver  from  the  cold.  It  requires, 
therefore,  much  less  solidity  than  the  other,  and  thus 
leaves  the  diver  greater  freedom  of  motion. 

MM.  Eouquayrol  and  Denayrouze  have  done 
everything  to  bring  their  incontestably  useful  ap- 
paratus within  the  reach  of  all.  Experiei^ced  and 
intelligent  divers  are  no  longer  requisite — neither  is 
it  necessary  to  employ  workmen  accustomed  by  long 
practice  to  work  the  pump  in  a  uniform  manner.  We 
have  already  seen  how  the  diver  is  enabled  to  obtain 
a  regular  supply  of  air  in  spite  of  any  irregularities 


PJiECAUTIONS  NECESSARY.  251 

in  working  the  pump.  The  substitution  of  a  simple 
mask,  in  place  of  the  helmet  hitherto  in  use,  allows 
the  dress  to  be  closed  hermetically  with  much  greater 
facility,  a  single  bolt  effecting  this  completely. 

There  are,  nevertheless,  several  precautions  neces- 
sary. If  these  are  not  ol^served,  the  miners  run  risks 
which  are,  to  say  the  least,  disagreeable.  The  pres- 
sure to  be  supported  increases  by  one  atmosphere 
for  every  32  feet  of  the  depth.  The  workman's  body 
is  therefore  under  a  pressure  of  about  four  atmospheres 
when  at  a  depth  of  100  feet,  whilst  at  the  surface 
he  would  be  under  the  pressure  of  one  only.  A  rapid 
transference  from  one  pressure  to  another  so  different 
cannot  be  effected  with  impunity.  But  the  body  will 
gradually  become  accustomed  to  these  new  physio- 
logical conditions,  if  the  man  begin  by  descending  a 
few  feet,  and  increasing  the  depth  day  by  day.  Even 
with  this  preliminary  training,  each  descent  should 
be  made  very  slowly.  The  return  should  be  even 
more  slow ;  and  to  avoid  all  inconvenience,  it  would  be 
well  to  allow  about  one  minute  for  every  six  or  seven 
feet  of  rise.  If  these  simple  recommendations  are  not 
followed,  much  suffering  may  be  caused — such  as 
singing  in  the  ears,  and  headache.  The  workman 
must  be  trained  gradually,  as  is  the  case  in  all  bodily 
exercises. 

The  light  is  verv  feeble  beneath  the  water,  and 


252  THE  BOTTOM  OF  THE  SEA. 

darkness  increases  with,  the  depth,  soon  becoming 
such  that  the  workman  has  to  grope  his  way  about — 
more  especially  where  the  bottom  is  muddy,  and  in 
parts  where  it  is  impossible  to  see  beyond  a  depth  of 
twelve  or  fifteen  feet.  To  remedy  this  serious  incon- 
venience, attempts  have  been  made  to  use  an  oil  or 
spirit-lamp,  and  even  a  simple  lantern  lighted  with  a 
candle.  A  pipe,  communicating  with  a  pump,  is 
needed  to  convey  the  air  necessary  for  combustion  ; 
another,  rising  to  the  surface,  permits  the  escape  of 
the  products  of  combustion.  Witliout  referring  to 
the  inconvenience  which  was  generally  I'elt  in  working 
these  lamps  and  their  two  pipes,  the  light  was  always 
found  insufficient.  The  dense  air  transmitted  by 
the  pumps  gave  rise  to  the  singular  phenomena  to 
be  observed  in  compressed  air-tubes ;  the  wicks  car- 
bonised, the  light  was  pale,  and  lasted  hardly  a 
quarter  of  an  hour.  These  difficulties  have  been 
overcome  by  employing  the  electric  light.  A  per- 
fectly watertight  lamp  of  iron  or  brass  encloses  the 
regulator  of  an  electric  light  on  Serrin's  system.  The 
wires  which  conduct  the  current  enter  the  lamp  by 
traversing  a  non-conducting  plug  of  tow.  The  current 
is  derived  from  a  pile  of  fifty  elements,  and  a  dazzling 
light,  equivalent  to  two  thousand  of  Carcel's  jets,  is 
obtained.  The  sides  of  the  lamp  resist  the  pressure 
exerted  by  the  water,  and  tlie  gases,  becoming  dilat^jd 


SUBMAIUSE  LIGHT. 


253 


by  tlie  heat,  escape  by  means  of  a  little  valve  analo- 
gous to  that  used  in  the  artilicial  lung. 

The  regularity  of  the  light  thus  obtained  depends 
only  on  the  regulator  itself,  and  not  at  all  on  the 
depth  ;  it  will  maintain  its  energy  for  about  tliree 
hours,  and  then  it  is  only  necessary  to  (hinge  tie 
carbon-points. 


Fig.  47. — Divere  finding  a  Box  of  Gold  in  the  Poit  of  Marseilles. 

Divers  are  very  generally  employed  to  recover 
things  which  have  fallen  into  the  sea.  How  many 
valuable  objects  have  been  rescued  fi-om  the  ocean 


254  THE  BOTTOM  OF  THE  SEA. 

by  this  means,  in  8[)ite  of  the  mud  or  sand  which  had 
ah'oady  commenced  to  cover  them  up!  The  diver, 
with  the  equipments  we  have  described,  makes  his 
investigations  in  perfect  safety  and  ease  ;  he  can  see 
quite  as  well  as  in  full  daylight;  he  examines  every 
cranny ;  he  overturns  the  soil  stone  by  stone ;  he 
maps  out  liis  field  of  operations,  and  thus  saves  him- 
self from  a  useless  repetition  of  his  seaich.  His 
patient  investigations  are  rarely  without  some  valu- 
able result.  In  the  excellent  desciiptiou  of  the 
Eouquayrol-Denayrouze  apparatus,  we  find  the  fol- 
lowing remarkable  example  of  a  salvage  effected  by 
the  help  of  this  apparatus : — 

"  The  packet-boats  Ganges  and  Vlmperatrice  came 
into  collision  in  the  outer  port  of  Marseilles.  The 
Imperatriee  had  one  of  her  wheels  broken,  and  the 
officers'  quarters  damage  1.  One  of  the  cabins  con- 
tained a  chest  full  of  gold,  which  fell  into  the  thick 
mud  which  forms  the  bottom  of  the  port  of  Marseilles. 
It  was  important  that  this  precious  package  should 
be  recovered  the  next  day.  The  sea  was  rough,  and 
the  exact  spot  where  the  accident  occurred,  unknown. 
The  box  was  not  strong,  its  colour  was  black.  At  the 
supposed  spot  a  plumb  of  60  kilogrammes  was  sunk. 
This  plumb  carried  two  cords  divided  into  meters ; 
two  divers  dragged  them  in  separate  directions,  and, 
taking  each  the  knot  corresponding  to  one  meter, 


I^HIPS  RAISED  AT  8EBA8T0P0L.  255 

they  described  consecutive  circles,  examining  the 
ground  at  each  step.  After  seeking  three  hours,  the 
gold  was  found  and  restored  to  its  owner,  who  had 
watched  the  operations  with  intense  anxiety.  This 
tealvage  was  effected  on  February  19,  1867,  by 
M.  Barbotin,  contractor  for  submarine  work  at  Mar- 
beilles." 

3.  Gowan's  Salvage  of  RuBsinn  Vessels  in  Sevastopol  Haibonr. 

An  American  engineer,  named  Gowan,  has  recently 
effected  a  much  more  important  salvage,  by  ex- 
plorations of  the  bottom  of  the  sea  of  greater  mag- 
nitude than  had  ever  been  attempted  before.  Prince 
Mentschikoff,  closely  besieged  in  Sebastopol  by  the 
Anglo-French  army,  perceiving  that  the  weak  point 
of  the  fortified  town  was  its  roadstead,  and  that  the 
vnemy's  fleet  was  about  to  force  an  entrance,  sank  a 
line  of  ships  and  frigates  in  the  passage  between 
I^'orts  Catherine  and  Alexander.  A  second  line  of 
vessels  was  sunk  to  fill  the  gaps  created  in  this  sub- 
marine barrier  by  the  autumn  storms.  At  hist,  when 
the  hour  for  the  liussian  retreat  had  arrived,  he  dis 
appointed  his  conquerors  by  sinking  all  that  remained 
of  the  fleet,  with  the  exception  of  a  few  solitary  barks, 
in  the  bay,  the  muddy  bottom  of  which  was  now  the 
bed  of  at  least  100  vessels,  representing  in  value 
8omo  fourteen  millions  sterling. 


256  THE  BOTTOM  OF  THE  SEA. 

The  vessels  thus  sunk  had  been  treated  in  such 
a  manner  as  to  resist  as  much  as  possible  the  dele- 
terious action  of  the  sea ;  any  part  likely  to  be  de- 
teriorated, such  as  the  engines  and  all  metallic 
fittings,  being  covered  with  tar  or  tallow.  Peace 
being  concluded,  ilie  struggle  was  commenced  be- 
tween man  and  the  sea.  Gowan  equipped  himself 
as  a  diver,  visited  and  examined  the  half-buried 
hulks  of  the  ships,  and  determined  that  the  sea 
should  yield  the  sunken  vessels;  some,  he  was  of 
opinion,  might  be  recovered  entire,  others  piece  by 
piece. 

An  enormous  pump,  raising  nearly  1000  tons  per 
minute,  was  used  to  withch-aw  the  water  from  the  in- 
terior of  the  vessels,  the  portholes  and  other  openings 
of  which  had  been  previously  imperfectly  closerl. 
This  powerful  machine  emptied  the  hulk  of  a  sub- 
merged vessel  in  a  very  short  space  of  time.  The 
lightening  was  so  sudden,  that  the  vessel  rose  to  the 
surface  before  the  water  had  time  to  re-enter  by  the 
various  openings  left.  An  enormous  chain,  1000 
feet  in  length,  each  link  in  which  weighed  150  kilo- 
grammes, served  as  an  auxiliary  to  this  pump,  or  when 
necessary  replaced  it  entirely.  To  conclude,  a  detacih- 
ment  of  divers  was  occupied  in  seeking  for  detached 
portions  of  wreck,  much  of  which  was  already  half- 
buried  in  mud. 


REPAIUING  SHIPS,  259 


4.  Ships  repaired  without  leaving  the-  Water,  and  even  while  under 
Sail. 

We  have  alrea'ly  mentioned  the  great  utility  of  the 
diving  apparatus  in  recovering  sunken  treasure,  and 
in  submarine  masonry  ;  but  its  utility  is  mu^-h  greater 
to  the  sailor  when  it  becomes  desirable  to  clean  or 
repair  the  bottom  of  his  vessel.  Every  day  increasing 
importance  attaches  to  the  parts  of  the  vessel  below 
water-mark.  Seagoing  steam-vessels,  especially,  re- 
quire the  frequent  employment  of  submarine  work- 
men. The  apparatus  formerly  used,  when  the  life  of 
the  man  depended  simply  on  the  strength  and  con- 
sistence of  his  dress,  was  but  little  adapted  to  the 
rude  buffetings  of  the  sea.  The  improved  diving- 
dress  which  we  have  just  described  is  far  from  pre- 
senting the  same  inconveniences. 

To  clean  or  repair  the  bottom  of  a  ship  it  is  no 
longej*  necessary,  as  heretofore,  to  lay  the  vessel  up 
in  dock,  and  thus  incur  great  expense,  as  well  as  the 
loss  ol  valuable  time.  A  rope-ladder,  with  rungs  ot 
wood  or  iron,  is  passed  under  the  vessel.  The  ladder 
having  been  stretched  tight,  the  diver  descends,  and 
clings  to  its  rungs  by  means  of  a  triangle,  the  base  of 
which  is  iron  and  the  two  sides  of  rope,  terminated 
by  an  iron  hook.  This  renders  the  use  of  his  hands 
iinnecessary  to  his  supjx)rt.      Pie  may  fill  his  airtight 


2G0 


THE  BOTTOM  OF  THE  SEA. 


clothing  with  air,  and  thus  be  in  a  manner  floated 
against  tne  overhanging  sides  of  the  ship  and  sus- 
tained without  any  trouble. 

'riie  American  monitor  Miantonomoh  returned  from 
Cronstadt   seriously   damaged ;    the   sailors   of    the 


Fig.  49, — Caulking  a  Ship  while  under  Fail. 


American  frigate  Colorado  repaired  tlie  vessel  in 
Cherbourg  Eoads,  during  rough  weather,  in  the  space 
of  five  days.  Cruising  in  the  Mediterranean,  the 
same  vessel  received  fresh  damage  in  a  pipe  at  the 


EXPERIENCES  OF  D  J  VERS.  2G1 

stem.     The  sailors,  provided  with  the  improved  ap- 
paratus, repaired  the  pipe  in  seven  hours. 

It  is  very  important  to  keep  the  bottoms  of  vessels 
cleansed  while  they  are  on  a  voyage,  especially  in 
hot  climates.  It*  the  apparatus  were  employed  hy 
passage-boats,  a  great  economy  of  coal  would  be  ef- 
fected. In  109  hours  of  labour  beueath  the  water, 
the  armour-plated  ram  Taureau,  which  had  been 
afloat  four  months,  an<l  the  bottom  of  which  was 
thickly  coveted  with  seaweed, little  shells,  and  muscles, 
was  completely  cleanse  1  ;  its  speed,  as  ascertained 
immediately  afterwards,  was  12J  knots  —  a  high 
rat<^  of  sailing  for  a  vessel  of  that  class. 


5.  Sensations  of  the  Diver — Depth  to  which  it  is  possible 
descend. 

There  is  a  limit  beyond  which  it  is  very  dangerous, 
not  to  siiy  impossible,  to  descend.  This  limit  is  at 
the  de}»th  of  about  200  feet.  The  diver  at  that 
depth  is  subjected  to  the  pressure  of  seven  atmo- 
splieres,  and  any  trifling  iticident  might  endanger 
his  life.  The  reader  will  find  a  curious  example  of 
this  in  the  Annates  de  Sauvetage  Maritime  (May, 
1866):- 

"On  February  17,  1865,  about  3  o'clock  in  the 
afternoon,   a  steamer  on  fire  was  sidited  oft*  Ushiu^t. 


262  THE  BOTTOM  OF  THE  SEA. 

The  vessel  was  low  down  in  the  water ;  it  was  dis- 
masted, and  had  lost  its  boats ;  it  sailed  under  a  top- 
sail,  gallant,  and  jib ;  the  other  sails  hung  in  shreds 
from  their  ropes.  Instead  of  anchoring  in  Stiff  Bay, 
situated  west  of  the  island  of  Ushant,  towards  which 
it  appeared  to  direct  its  course,  this  illfated  vessel 
got  entangled  in  the  rocks  betu  een  one  of  the  points 
of  this  bay  an  1  the  Men-Corn,  and  very  shortly 
grounded.  The  sailors  were  seen  to  run  about  the 
deck  as  if  they  were  mad.  The  sea  was  lumpy,  wind 
violent  in  the  extreme;  no  help  could  reach  them 
from  tlie  land,  as  neither  a  rope  nor  the  means  of 
throwing  one  on  board  coul  1  be  procurtd.  The  rising 
ti  le  soon  floated  the  vessel,  now  deprived  of  her 
rudder,  however,  which  had  been  broken  on  the 
rocks ;  and  being  at  the  mercy  of  the  winds  and  cur- 
rents, she  drifted  into  the  Helle  channel.  It  now 
appeared  that  she  had  sprung  a  leak,  as  her  stern 
gradually  settled  down,  and  an  hour  afterwards  the 
vessel  was  wholly  engulfed,  just  as  darkness  hid  her 
from  view.     This  ship  was  the  Columbia. 

"  Left  Mol5ne  on  the  31st  of  August,  at  half-past  4 
in  the  morning.  About  11  o'clock  the  pilots  grappled 
what  they  believed  to  be  the  Columbia.  The 
Flambeau  moored  herself  by  four  anchors  as  nearly 
as  possible  at  the  spot  indicated.  A  sounding  taken 
by  tiie  captain  gave  180  feet  as  the  depth  to  the 


EXPERIENCES  OF  DIVERS  263 

deck  of  the  wreck ;  tlie  lead  indicated  pit-coal,  red 
lead,  and  black  paint  The  bottom  to  the  south- 
I'ast  of  the  ship  was  about  200  fe  t ;  to  the  north- 
west about  230  feet.  The  northernmost  anclior  was 
at  a  depth  of  250  feet.  The  four  anchors  were  laid 
down  by  1  o'clock.  While  tlie  men  dive  we  pre- 
pare the  battery  and  the  lamp,  whicli  burns  well  in 
the  air.  The  pumps  and  other  apparatus  are  got  in 
order.  At  25  minutes  past  8  the  diver,  Deschamps, 
has  his  mask  fitted  on. 

"The  following  is  his  own  description  of  the 
impressions  he  received  in  his  two  descents  : — 

"  First  Trial. — He  descends  step  by  step,  resting  at 
intervals,  and  receiving  and  transmitting  the  signals 
with  regularity.  At  the  fiftieth  step,  water  enters 
by  the  back  valve,  which  he  closes  a  little ;  at  the 
sixtieth  he  closes  it  entirely ;  at  the  hundred-and- 
twentieth  (130  feet)  the  water  enters  by  his  front 
valve,  which  he  closes  a  little.  He  asks  for  more 
air.  At  the  hundred-and-sixtieth  step  (180  feet) 
he  makes  a  rather  longer  pause ;  he  sliuts  his  valve 
still  closer;  the  air  issues  only  by  bubbles.  He 
counts  174  steps ;  the  ladder  does  not  reach  the 
ground;  he  can  feel  and  distinguish  the  cast-iron 
weights  which  serve  to  stretch  the  ladder;  he 
hangs  by  them  and  rests  his  feet  on  the  ground — a  soft 
sand,  into  which  he  sinks.     Just  as  he  stoops  to  pick 


264  TUJ£  BOTTOM  OF  THE  SEA. 

up  something  white,  like  a  pebble,  he  feels  himself 
raised  with  great  rapidity,  and  his  feet  strike  against 
each  rung  in  the  ladder ;  he  holds  the  ladder  with 
one  hand,  but  cannot  succeed  in  grasping  it  with 
the  other.  An  accident  has  happened  to  the  pumps, 
and  he  has  not  been  in  any  way  conscious  of  it. 
At  the  fiftieth  step  he  loses  sight  of  the  lamp  and 
wires;  they  had  appeared  to  him  like  ordinary  thin 
brass  wires.  On  touching  the  ground  he  ielt  the 
water  enter  at  his  right  foot. 

"  Second  Trial. — At  the  fortieth  step,  water  enters 
by  the  back  valve ;  he  screws  it  up  a  little,  and  is 
obliged  to  close  it  at  the  sixtieth.  At  160  feet, 
water  enters  by  the  front  valve,  which  he  holds 
nearly  closed.  At  195  feet,  water  enters  by  his  leg ; 
he  closes  the  valve  and  rests  on  the  sand,  in  which 
his  feet  sink.  The  pressure  is  general  over  the 
whole  body,  and  is  exerted  on  the  bladder,  which 
empties  itself  involuntarily.  This  effect  had  also 
been  produced  with  less  intensity  when  he  reached 
the  ground  the  first  time.  He  detaches  one  end  of 
his  guide-cord;  he  can  distinguish  this  cord,  the 
weights,  his  hands,  and  he  advances  a  few  steps. 
He  has  great  difficulty  in  withdrawing  his  feet  from 
the  sand,  to  which  he  feels  rooted.  All  at  once  his 
sight  is  obscured,  his  head  turns;  he  returns  in- 
stinctively to  the  ladder,  and  asks  to  be  raised.     He 


EXPERIENCES  OF  DIVERS.  265 

begins  to  ascend  as  well  as  his  strength  will  allow ; 
feels  himself  impeded  by  his  guide-cord,  which  he 
cuts ;  and  then  rises  alone  very  rapidly,  having  lost 
his  senses.  A  violent  shock  brings  him  to ;  he 
recognises  the  sides  of  the  ship,  against  which  his 
mask  has  struck,  and  regains  his  courage.  He  waves 
his  hand  over  tlie  surface  of  the  water,  and  feels  him- 
self sinking.  His  mask  having  got  displaced,  the 
collar  almost  chokes  him.  He  feels  himself  seized 
by  the  arms,  and  grasps  a  rope  which  his  hand  hap- 
pened to  touch.  He  again  loses  consciousness  for  a 
moment  in  the  ship's  boat,  and  asks  to  be  raised  on 
deck  as  soon  as  his  mask  shall  be  unscrewed.  He 
supers  much  from  the  right  hand,  breathes  with 
difficulty ;  his  extremities  are  cold,  and  neck  painful. 
Twice  he  nearly  faints,  and  ceases  to  breathe.  His 
sight  appears  troubled,  everything  turns  round  with 
him,  and  his  gaze  has  no  steadiness. 

"  We  unanimously  concluded  that  the  state  of  the 
diver  and  his  apparatus  proved  that  neither  could 
work  with  regularity  under  a  pressure  of  six  atmo- 
spheres, and  that  it  would  be  very  impiudent  to 
expose  the  lives  of  men  by  causing  them  to  work 
under  this  pressure.  The  diver  wished  to  repeat  th« 
attempt,  but  neither  the  captain  nor  the  engineers 
would  permit  him  to  do  so.  The  above  experiments 
show  that  the  diver   may  breathe,  that  his  organs 


266  TUE  BOTTOM  OF  THE  SEA. 

may  remain  in  their  normal  state,  and  he  may  pre- 
serve his  presence  of  mind,  to  a  depth  of  130  feet ; 
but  when  he  exceeds  this  depth  by  10  or  20  feet, 
the  external  pressure  causes  physiological  effects  on 
his  organs  independent  of  his  will.  One  hundred 
and  thirty  feet  is  therefore  the  depth  which  experi- 
ment shows  to  be  the  greatest  at  which  any  hope 
can  be  entertained  of  performing  any  prolonged 
submarine  work.  .  .  .  Within  this  limit,  security  to 
life  is  perfectly  compatible  with  the  conditions  in- 
volved in  an  attempt  to  recover  any  ship  or  sunken 
treasure  which  will  pay  the  necessary  expenses. 

(Signed)  '*  Carvallo." 


6.  Extreme  difficulty  of  working  below  Water — Submarine  founda- 
tions— Stone  worked  when  in  position. 

It  appears  from  what  we  have  stated  above,  that, 
notwithstanding  all  the  efforts  of  genius,  we  cannot 
penetrate  the  oceanic  abysses.  Nearly  all  that  we 
can  do  must  be  done  on  the  borders  of  the  vast  ex- 
panse. Nevertheless,  our  visits  to  the  sea,  though 
limited,  have  a  great  theoretical  and  practical  im- 
portance, of  which  we  have  already  cited  numerous 
examples. 

The  art  of  diving  is  almost  indispensable  in  build- 
ing submarine  constructions.     What  great  work  can 


SUBMARINE  MASON liY.  267 

a  man  perform  who  works  in  the  (^ark,  casting  Iiis 
materials  nl  nost  haphazard  into  the  lap  of  an  ele- 
ment which  de  dares  not  or  cannot  grapple  with? 
Would  his  labours  be  much  more  valuable  if  he  had 
to  dive  and  leave  the  water  every  instant,  throwing 
only  a  coup  d'oeil  over  the  work  which  he  could  not 
wait  to  improve  or  advance  ? 

When,  by  continuous  efforts,  and  by  the  use  of  an 
immense  amount  of  materials,  man  shall  have  built 
up  a  foundation  in  the  bed  of  the  sea,  he  will  still 
find  himself  continually  arrested  by  the  difficulty  of 
making  permanent  progress  at  the  surface.  In  calm 
weather  his  building  goes  on  apace ;  he  is  pnjud  of  it, 
and  regards  the  sea  as  a  subjugated  enemy.  But 
the  furious  waves  of  a  sudden  tempest  breaks  down 
his  work  as  if  by  enchantment,  as  if  it  had  deter 
mined  to  crush  man  with  the  greater  humiliation 
for  having  allowed  him  sufficient  re>pite  to  make 
such  arduous  progress. 

The  beautiful  breakwater  at  Cherbourg,  one  of 
the  most  gigantic  of  modern  undertakings,  had  been 
thrown  down  many  times  by  t!ie  sea  before  it  stood 
in  its  invincible  strength  to  form  an  impassable 
barrier  to  the  fury  of  the  waves.  Such  works  were 
formerly  built  by  casting  into  the  sea  at  the  chosen 
site  a  vast  number  of  immense  boulders,  stones,  and 
concrete,  piling  them  up  in  the  irregular  pell-melJ 


208 


THE  BOTTOM  OF  THE  SEA. 


fiisliioii  attributed  to  the  giants  in  the  fable  when 
seeking  to  scale  the  heavens.  Tliese  works  are 
now  effected  with  less  precipitation  and  infinitely- 
more  studied  circumspection;  enormous  blocks  are 
built  one  upon  another,  upon  which  the  sea  mav 
exercise  its  utmost  fury  in  vain.     These  blocks  an^ 


Fig.  50. — Siuking  Blocks  of  artificial  Stone  at  Cherbouig. 

manufactured  on  the  spot,  by  filling  enormous  rec- 
tangular caissons  with  a  kind  of  coarse  concrete, 
which  liardens  by  contact  with  the  air,  and  par- 
ticularly with  water  (fig.  50). 


WORKS  AT  CnERBOURG.  269 

Wlien  tiie  block  is  sufficiently  solidified  to  bear 
submersion,  the  mould  is  removed  and  the  block  is 
sunk  into  the  sea.  But  the  diver  must  have  first 
prepared  the  foundations  of  this  cyclopean  wall  on  a 
perfect  level.  Provided  with  levers  aud  other  tools, 
he  raises  the  block,  and  places  it  in  the  exact  position 
indicated  by  the  engineer.     The  care  demanded  by 

Ilaibour  p^.^..n.p,^.^i^  -g       Level  of  tlie  sea  at  InVh-tide. 


Fig.  51. — Vertical  Section  of  Breakwater  at  Cherbourg. 

A.  Rock  work  of  von  gh  stones,  D.  Foundation  of  artificial  stone. 

B.  Unwroiight  blocks.  E.  Wall  laid  in  liydraulic mortal*. 

C.  Blocks  of  squared  stone.  F.  Granite  facing. 

this  process  renders  it  necessary  that  the  divers 
should  be  continually  descending  and  ascending,  in 
order  to  examine  the  work  on  all  sides.  Furnished 
with  the  apparatus  we  have  described,  they  can,  by 
means  of  a  simple  tap,  fill  or  empty  their  caoutchouc 


•i-zo  tbFj  bottom  of  the  ska. 

clothiDg  of  the  air  it  contains,  and  thus  make  it 
answer  the  purpose  of  a  swimming-bladder.  They 
may  manoeuvre  in  the  most  varied  manner  when 
beneath  the  water  by  simply  turning  a  tap.  The 
blocks  of  stone  are  thus  built  up  with  as  much 
regularity  as  on  dry  land,  and  are  capable  of  oppos- 
ing the  greatest  possible  resistance  to  the  incessant 
attacks  of  the  waves. 


7.  Diving  Bells — Stationary  Compressed-air  Apparatus. 

Previous  to  the  invention  of  the  apparatus  which 
we  have  now  described  at  some  length,  diving-bells 
were  employed  in  the  construction  of  jetties,  fortifica- 
tions, lighthouses,  docks — in  a  word,  in  all  important 
submarine  work.  This  invention  consists  of  a  large 
cast-iron  bell,  communicating,  at  its  upper  part,  with 
a  force-pump. 

Invert  a  common  drinking-glass  in  a  basin  of  water ; 
the  air  diminishes  in  volume  as  the  glass  is  sunk 
further  in  the  water ;  indeed,  its  bulk  may  be  seen  to 
decrease  by  the  gradual  rise  of  the  water  in  the 
glass.  The  air  collects  in  the  upper  part  of  the  glass, 
and  becomes  gradually  more  compressed — preventing 
the  water,  however,  from  completely  tilling  the  vessel. 
Make  a  communication  between  the  bottom  of  the 
glass  and  a  reservoir  of  air  compressed  to  the  same 


DIVING  BELLS.  271 

extent  as  that  in  the  ^hiss,  the  water  still  leniaining 
at  the  same  level.  Compress  this  somewhat  more, 
it  drives  the  water  from  the  gla.-8,  which  it  fills.  This 
is  precisely  what  happens  in  the  diving-bell. 


Fig.  52.— Diving  Bell. 

While  the  bell  descends  the  workmen  are  supported 
on  transverse  benches.  Havino^  reached  the  bottom, 
the  air  from  the  pump  drive  s  out  all  the  water  from 
the  bell,  and  the  men  can  then  leave  their  seats  and 
commence  work.     As  they   cannot  leave  the   bell, 


272  THE  BOTTOM  OF  THE  SEA. 

the  field  of  tlieir  operations  is  necessarily  limited — 
an  inconvenience  which  is  remedied  by  moving  the 
bell  laterally.  In  fact,  tliis  inconvenience  is  only 
nominal  when,  as  is  often  the  case,  the  labour 
consists  in  making  an  excavation  in  one  particular 


Fig.  53. — Fixed  .Apparatus,  supplied  with  Compressed  Air. 

spot.  In  such  cases  the  diving-bell  may  be  even 
advantageously  replaced  by  apparatus  employing 
compressed  air,  and  of  such  a  form  as  the  conditions 
of  the   work   demand.     It  was  by  the  exercise  of 


CONSTRUCTION  OF  BRIDGES.  273 

ingenuity  in  this  respect  that  the  magnificent  bridge 
over  tlie  Khine,  near  Strasbourg,  was  so  rapidly  con- 
strutted. 

Each  of  the  piers  of  this  bridge  rests  on  a  founda- 
tion composed  of  four  iron  caissons  of  large  size  and 
weight.  Each  caisson  was  open  at  its  lower  part 
(fig.  53).  The  upper  part  supported  three  shafts, 
a  middle  and  two  lateral  ones.  All  three  rose  above 
the  surface  of  the  waters  of  the  Rhine.  The  middle 
shaft  communicated  with  the  open  air,  and  the  water 
rose  in  it  to  the  general  level  of  the  river.  It  enclosed 
a  dredging-apparatus  worked  by  a  steam-engine. 
This  dredge,  as  well  as  the  shaft  itself,  descended  to 
the  bottom  of  the  river.  The  workmen  loaded  the 
compartments  of  the  dredge,  which  discharged  its 
load  into  the  river. 

The  two  lateral  shafts  terminated  at  the-  upper 
part  of  the  caisson.  The  workmen  first  shut  them- 
selves up  hermetically  in  the  upper  part  of  the  shaft, 
which  they  afterwards  put  in  communication  with 
blowing-machines.  The  compressed  air  driven  by 
these  machines  gradually  expelle  I  the  air  from  the 
shaft,  and  ultimately  from  the  caisson,  into  which  the 
workmen  would  now  descend  and  commence  their 
excavations,  carrying  the  debris  to  the  dredges. 
When  the  workmen  wish  to  leave,  they  first  monnt 
to  the  upper  part  of  the  lateral  shaft ;  the  action  of 


274  THE  BOTTOM  OF  THE  SEA 

the  blowing-machine  is  then  gradually  lessened,  so 
as  to  diminish  by  degrees  the  pressure  of  the  air  they 
breathe.  The  water  rises  at  the  same  time  in  the 
caissons  and  lateral  shafts  until  it  has  attained  the 
level  of  the  river.  The  dour  is  then  opened  and  the 
men  leave  their  prison,  Avhich  may  be  regarded  as 
a  species  of  diving-bell,  but  of  a  form  devise  I  for  a 
special  service. 


8.  Ptiyerne's  Submarine  Hydrostat 

The  diving-bell  proper  has  been  much  improved  by 
M.  Payerne.  His  *'  Submarine  Hydrostat "  possesses 
the  immense  advantage  of  being  capable,  at  the  will 
of  those  enclosed  in  it,  either  of  floating  on  the  sur- 
face, or  of  sinking  or  rising,  as  may  be  desired. 
Thirty  men  may  work  in  it  with  ease  for  a  number 
of  hours  without  inconvenience.  It  is  therefore  oj 
great  service  in  clearing  ports,  and  in  facilitating  the 
execution  of  other  submarine  work. 

The  principle  of  the  machine  is  very  ingenious. 
Externally,  it  has  the  appearance  of  one  large 
rectangular  box,  surmounted  by  another  smaller 
one,  completely  closed  in  except  at  the  bottom. 

The  interior  of  the  hydrostr.t  consists  of  three 
principal  compartments.     The  lower,  or  hold,  is  open 


PAYERNE'S  HTDROSTAT.  275 

below,  as  just  stated,  and  communicates  by  a  large 
chimney,  or  shaft,  with  the  upper  compartment,  or 
hetween-decks.  Between  these  is  a  third  compartment, 
or  orlop-deck,  which  only  communicates  with  the 
others  by  means  of  stopcocks.  All  round  the  hold 
and  the  orlop-deck  runs  a  gallery,  hermetically 
closed,  and  connected  with  the  former  compartments 
by  stopcocks  only.  The  lower  part  of  the  gallery 
receives  the  ballast  of  the  machine,  whilst  the  uj)per 
is  filled  with  air  or  water  as  occasion  requires.  (Fig. 
54.) 

Whilst  the  hydrostat  floats,  the  hold  and  one  por- 
tion of  the  shaft  are  full  of  water ;  the  orlop-deck,  its 
gallery,  and  the  hetween-decks  being  full  of  air.  A 
lift  and  force-pump  are  found  in  the  latter,  where 
the  workmen  would  now  be  stationed. 

When  it  is  wished  to  sink  the  hydrostat,  the  hatch 
of  the  between-decks  and  the  dooi-  of  the  shaft  are 
closed  hermeti(;ally.  The  pump  is  worked  in  such  a 
manner  as  to  draw  water  from  the  exterior,  and  fill 
the  orlop-deck  and  its  galleiy.  A  pipe  furnished 
with  a  stopcock  allows  communication  between  the 
upper  part  of  the  orlop-deck  and  the  hold.  At  the 
Kanie  time  that  the  latter  is  filling  with  compressed 
air,  the  apparatus  fills  with  water,  gets  heavier,  and 
ultimately  sinks.  The  water  which  was  in  the  hold 
has,  it  is  true,  been  expelled ;    but  the  contents  of 


27G 


THE  BOTTOM  OF  THE  SEA. 


this  compartment  are  equal  to  that  of  the  orlop-deck. 
The  hold  was  originally  full  of  water,  but  now  both 
the  orlop-deck  and  the  gallery  are  full.  The  work- 
men now  open  the  door  of  the  shaft  and  descend 
into  the  hold,  having  the  bottom*  of  the  sea  lor  a 


^ 


FiiT.  54. — Paverne's  Submarine  Hvilrostat. 


floor,  and  the  scene  of  their  labours.  One  or  two 
remain  in  the  between-decks,  there  to  store  away 
the  excavated  material,  and  work  the  pump  when 


neces-a»v. 


PA  ¥£3X178  HTDROSTAT.  277 

When  they  wish  to  rise  again  to  tho  surface,  the 
men  re-enter  the  hetween-dechs  by  the  shaft,  which 
they  close  hermetically.  The  pump  is  worked  so  as 
to  withdraw  the  air  from  the  hold,  and  transmit 
it  to  the  orlop-deck  and  gallery.  The  water  escapes 
by  the  pipe  communicating  with  the  exterior.  The 
hydrostat  becomes  lighter  as  the  hold  fills  with 
water,  and  soon  floats  on  the  surface  as  before.  The 
men  then  open  tlie  hatch^  and  obtain  communication 
with  the  outer  world.  The  hydrostat  is  removed 
from  one  spot  to  another  by  towing. 

The  hold  is  square.  It  measures  about  26  feet  in 
the  side,  by  6  feet  6  inches  in  depth.  The  orlop-deck 
has  the  same  dimensions.  The  hetween-decJis  has  the 
same  depth,  but  measures  only  16  feet  in  the  side. 
The  hydrostat  is,  therefore,  nearly  20  feet  in  height, 
and  its  base,  which  has  the  bottom  of  the  sea  for  a 
floor,  covers  an  area  of  625  square  feet.  We  have 
already  stated  that  an  airtight  gallery  surrounds  both 
the  lower  storeys.  This  gallery,  like  the  orlojp-dech, 
is  divided  into  a  number  of  smaller  compartments, 
which  can  be  made  to  communicate,  or  kept  distinct, 
by  means  of  stopcocks. 

M.  Payerne's  submarine  hydrostat  resolves  several 
difficulties  at  once.  By  interior  arrangements,  as  we 
have  seen,  it  may  be  made  to  rise  or  fall  at  will,  and 
it  will  readily  float  about  like  a  raft.     This  ingenious 


27S  THE  BOTTOM  OF  TUB  SEA. 

machine  has  already  been  put  to  the  test.  The  port 
of  Fecamp  was  choke  I  up  with  shingle,  which  closed 
it  against  all  vessels  beyond  a  certain  tonnage.  The 
hydrostat  was  emplo3^ed,  and  the  port  cleaned  and 
again  opened  to  commerce.  The  cases  in  which  it 
might  be  employed  with  advantage  are  obviously 
very  numerous. 

Ports  are  more  generally  made  by  digging  vast 
basins  in  the  neighbourhood  of  coasts  than  by  seeking 
to  enclose  portions  of  the  sea  by  means  of  jetties. 
The  work  is  more  easily  and  quickly  done  in  the 
open  air,  and  there  is  not  the  probability  that  the  sea 
will  overturn  it  at  any  moment.  The  port  enclosed 
by  hills,  or  the  natural  port,  has  the  double  advantage 
of  giving  shelter  both  against  wind  and  wave.  But  if 
the  port  fill  up  gradually,  if  its  mouth  become 
obstructed  by  mud  or  sand  washel  up  by  the  sea, 
the  hydrostat  may  be  advantageously  employed. 

9.  Villeroy's  Submarine  Boat, 

What  ingenuity  has  been  brought  to  bear  on  the 
construction  of  submarine  engines,  both  for  purposes 
of  destruction  and  investigation!  Boats  to  sail  be- 
neath the  water,  diving-bells  and  dresses,  submarine 
fireships  and  torpedoes,  are  all  so  many  evidences  of 
the  activity  developed  in  the  human  mind  by  the  sea. 


riLLEROTS  SUBMARINE  BOAT. 


270 


M.  Villeroy,  a  French  engineer,  constructed  at 
Philadelphia,  a  few  years  ago,  a  remarkable  machine, 
intended  to  swim  at  any  de[)th  beneath  the  surface 
of  the  sea  that  its  conductor  might  desire.  This  sub- 
marine vessel  was  shaped  like  a  cylinder,  with  conical 


Fig.  55. —  \'ill-'ruy's  Sibmarinc  Boat. 

ends.  It  was  closed  hermetically.  It  was  lighted 
by  a  large  number  of  circular  windows  cut  in  its  iron 
skin,  and  closed  up  with  thick  glass.  A  hatchway 
allowed  ingress  and  egress.  Gutta-percha  tubes, 
placed  in  the  interior,  communicated  with  the  exterior 


280  THE  BOTTOM  OF  THE  SEA. 

by  means  of  a  conduit-tube  furnished  with  a  stop- 
cock. By  means  of  a  pump  the  vessel  could  be  filled 
with  water  at  will.  To  cause  tlie  vessel  to  sink  it 
was  only  necessary  to  allow  the  water  to  penetrate 
these  tubes ;  its  ejection  caused  the  vessel  to  rise.  A 
screw  worked  at  the  stern. 

Villeroy's  structure  was  35  feet  in  length,  and  44 
inches  in  diameter.  Tlie  screw  was  3  feet  in  diameter. 
By  lighting  the  bottom  of  the  sea  by  means  of  an 
electric  light  placed  in  the  interior  of  the  vessel,  a 
convenient  method  of  exploration  would  be  obtained, 
at  least  in  the  neighbourhood  of  the  coasts. 

This  vessel,  built  during  the  American  war  contem- 
poraneously with  the  production  of  the  monitors, 
which  may  be  said  to  have  saved  the  North  from  the 
humiliation  of  defeat,  is  a  worthy  companion  of  the 
torpedo — that  terrible  instrument  of  war,  which,  in  a 
moment  of  supposed  security,  is  capable  of  destroying 
the  most  formidable  ship  of  war  with  even  more  cer- 
tainty than  a  tempest. 


10.  Employment  of  Torpedoes  in  clearing  Channels  and  the 
Entrances  to  Ports. 


In  our  age — which  may  be  called  an  age  of  progress, 
since  it  has  witnessed  the  development  of  so  many 


TORPEDOES.  281 

ideas  which  illustrate  the  fraternity  of  men,  and  the 
solidarity  of  their  interests,  without  which  we  are 
little  superior  to  the  brutes — how  many  instruments 
of  destruction  have  been  converted  from  their 
original  design  in  the  interests  of  our  common 
humanity,  and  applied  to  beneficent  purposes! 
Manby  in  England,  and  Delvigne  in  France,  have 
transformed  the  cannon  into  an  instrument  for  the 
salvation  of  life,  so  that  the  destructive  missile  is 
hurled  through  the  air  as  a  messenger  of  hope  to 
the  shipwrecked  crew,  by  carrying  the  thread  on 
which  depends  their  safety.  In  the  same  spirit, 
Tixier  has  employed  the  torpedo  as  an  instrument  of 
salvation.  The  Dunkirk  PM  mentions  an  opera- 
tion, the  perfect  success  of  which  leaves  no  doubt 
of  the  happy  results  we  may  expect  from  the  ser- 
vices of  this  terrible  yet  docile  auxiliary  of  man. 

The  schooner  Virginiey  of  St.  Malo,  sunk  at  the 
entrance  to  that  port  by  the  steamboat  Zingariy  was 
partly  broken  up  by  a  torpedo  exploded  in  its  hold 
by  M.  Franfois  Tixier,  who  undertook  this  operation 
and  brought  it  to  a  successful  termination.  The 
various  phases  of  the  explosion,  up  to  the  time  which 
would  elapse  between  igniting  the  Bickford  fuse 
and  the  result  itself,  had  been  previously  indicated 
with  remarkable  precision,  which  the  result  fully 
confirmed,   and   which    was  attested  by  numerous 


2S2 


THE  BOTTOM  OF  THE  SEA. 


spectators.  The  explosion,  which  caused  a  tremen- 
dous upheaval  of  the  water  and  pieces  of  wreck, 
accompanied  with  quantities  of  sand,  was  received 
with  acclamations  by  the  spectators,  as  a  demonstra- 
tion that  the  expectations  of  the  operator  had  been 


Kig.  56. — Removing  an  Obstruction  by  means  of  a  Torpedo. 

fulfilled.  This  experiment  proves  that  we  have, 
even  now,  an  important  addition  to  our  means  of 
removing  the  debi^is  arising  from  disasters  similar  to 
the  above,  the  number  of  which  has  increased 
greatly  of  late  years.     The  whole  of  the  wreck  may 


REMOVING  OBSTBUCTIONS.  2Sr> 

thus  be  removed  piecemeal,  until  the  passage  shall 
have  been  completely  cleared,  and  the  possible  cause 
of  many  serious  accidents  removed. 

It  is  seldom  that  so  powerful  an  instrument  as  the 
torpedo  is  necessary,  but  submarine  blasting  is  often 
resorted  to ;  and,  in  such  cases,  a  diver  comes  into 
requisition.  He  directs  the  apparatus,  worked  either 
by  hand  or  steam-power,  and  prepares  the  ground 
for  the  introduction  of  the  destructive  agent.  When 
the  hole  is  made  he  inserts  the  iron  vessel  filled  with 
powder  or  nitro-glycerine.  He  covers  it  with  cement, 
and  places  it  in  communication  with  the  shore,  by 
means  of  conducting  wires  for  the  electric  current, 
or  a  fuse  which  will  burn  under  water.  The  diver 
then  retires.  Either  the  fuse  is  lighted,  or  an 
electric  current  is  sent  through  the  wires,  and  the 
explosion  takes  place. 

At  great  depths  the  action  of  the  powder  is  pro- 
digious. Compressed  by  a  column  of  water,  the 
gases  exert  an  increased  force  on  the  rock  (if  that 
be  the  nature  of  the  obstruction),  and  tear  it  in  a 
thousand  directions.  At  the  surface  there  is  scarcely 
any  indication  of  the  concussion  below,  except  a 
slight  agitation  of  the  water.  Dead  fish  float  about 
the  scene  of  action,  and  a  hollow  sound  is  heard. 
If,  however,  the  depth  of  the  water  be  sliglit,  the 
explosion  causes  the  projection  of  a  jet  into  the  air. 


284  THE  BOTTOM  OF  THE  SEA. 

and  the  rock  is  less  affected  by  it.  For  this  reason, 
where  there  is  a  tide,  the  operators  await  the  period 
when  it  is  at  its  highest  before  firing  the  charge. 
This  precaution  is  more  than  ever  necessary  where 
the  rock  is  broken  up,  and  it  is  sufficient  to  take 
advantage  of  its  natural  crevices  and  employ  a  charge 
npplied  in  bottles. 


11.  English  Mines  beneath  the  Ocean. 

Man's  submarine  labours  are  not  limited  to  the 
surface  of  the  sea-bottom.  Nature  hides  some  of 
her  treasures  beneath  the  sea  as  well  as  beneath 
mountains.  Coal,  iron,  tin,  and  other  minerals  are 
often  obtained  from  great  depths.  A  vertical  shaft 
affords  communication  with  the  horizontal  galleries 
from  which  the  mineral  is  extracted.  At  several 
points  of  the  English  coast  the  miner  does  not  hesi- 
tate to  carry  his  galleries  beneath  the  sea,  at  the 
risk  of  being  drowned,  if  the  least  fissure  permits 
the  ingress  of  water.  But  this  danger  is  also  en- 
countered in  ordinary  mines,  for  the  immense  bodies 
of  water  knov^'n  to  exist  in  the  crust  of  the  earth 
would  be  much  more  than  sufficient  to  destroy,  in  an 
instant,  the  most  gigantic  subterranean  works.  The 
enterprise  is  not,  therefore,  so  hazardous  as  might 
appear  at  first  sight ;  it  presents  in  other  cases  about 


MINES  BENEATH  THE  OCEAN.  .  285 

the  same  amount  of  difficulty.  Fire-damp  is  as 
dangerous,  and  its  effects  are  as  disastrous  in  the  one 
case  as  in  the  other.  Kindled  beneath  the  sea,  it  soon 
bursts  its  rocky  barriers;  the  fire  spreads,  an  ex- 
plosion destroys  the  walls  of  the  subterranean  chan- 
nel, entire  hills  are  lifted  or  overthrown  as  by  a 
volcanic  eruption.     It  is  of  little  consequence  to  the 


Fig.  57. — Section  of  a  Tin  Mine  in  Coraw-nll, 

miner  that  this  catastrophe  takes  place  under  the 
sea ;  the  danger  is  not  greater  than  if  it  happened 
in  the  middle  of  a  continent.  Before  being  drowned, 
he  would  be  burnt  or  crushed.  Let  us  reserve  our 
compassion  for  the  poor  sailor,  who  congratulates 
himself  upon  having  reached  an  hospitable  coast, 
and  suddenly  sees  his  vessel  scattered  to  the  winds 
and  waves  by  the  violence  of  a  submarine  explosion. 


286  THE  BOTTOM  OF  THE  SEA. 


CHANGES  IN  PROGKESS  AT  THE  BOTTOMS  OP  SEAS 
—THEIR  UNIVERSALITY. 


1.  Extent  of  the  movements  of  the  Terrestrial  Crust— Nature  in- 
cessantly at  work — The  gradual  Cooling  of  the  Earth  a  cause  of 
its  present  form,  owing  to  the  crumpling  and  breaking  of  its 
Crust. 

Everything  material  is  mutable:  continuity  of 
change  is  the  great  law  of  nature.  From  the  subtlest 
gas  which  escapes  our  visual  observation,  to  the  solid 
rock,  all  is  subject  to  movement  and  transformation. 
The  smallest  atom  and  the  mightiest  solar  system 
alike  obey  the  laws  of  gravitation,  and  move  on  in 
cycles  of  endless  progression.  The  modifications 
which  everything,  small  and  great,  in  the  physical 
world  is  undergoing  may  be  more  or  less  apparent, 
more  or  less  rapid ;  but  whether  it  be  or  be  not  de- 
monstrable to  the  sense,  it  takes  place  all  the  same, 
so  that  we  may  truly  say  that  all  matter,  however 
apparently  dead,  pulsates  with  life. 

Animals  and  plants  are  born,  grow,  and  die.  The 
elements  which  concur  towards  their  formation  and 
development  are  incessantly  renewed.  Having  accom- 


ALL  THINGS  MUTABLE.  2£7 

plished  their  part  in  the  organisation  to  which  they 
bad  accrued,  they  are  rejected,  and  their  place  taken 
by  others.  At  a  given  moment  they  are,  so  to  say, 
shunted  off  the  track  they  had  followed,  and  moved 
on  a  line  to  contract  new  alliances.  To  the  being 
with  whose  existence  they  were  identified  succeeds 
another,  totally  different ;  instead  of  the  concentra- 
tion of  force,  there  reigns  for  awhile  anarchy  ;  and 
anarchy  is  followed  by  the  rise  of  fresh  organisations, 
destined  in  their  turn  to  disappear.  There  is  no 
organised  being  that  is  immutable,  any  more  than  a 
simple  atom  that  is  so. 

In  like  manner  we  learn  from  history  that  whole 
peoples,  or  national  individualities,  are  born,  grow, 
and  die,  like  individual  men,  to  be  succeeded  by 
others.  Nay,  even  the  species  is  no  exception  to  the 
law  of  everlasting  change. 

But  at  least,  you  will  say,  the  solid  rock  is  allowed 
to  repose  in  quiet,  and  enjoy  the  privilege  of  im- 
mutability ?  No ;  its  surface  is  exposed  to  the 
action  of  all  manner  of  exterior  influences,  and  eve 
every  variation  of  temperature  profoundly  affects 
that  apparently  unchangeable  mass.  The  truth  is, 
our  view  of  things  is  a  very  limited  one.  The  in- 
finitely great  escapes  us  as  well  as  the  infinitely 
little.  Kven  a  wheel  moving  with  great  raj)idity 
seems  as  if  it  did  not  move.     Again,  an  extremely 


288  THE  BOTTOM  OF  THE  SEA 

slow  movement  of  the  same  wheel  would  not  b« 
observed. 

The  air  is  composed  of  a  great  number  of  elements. 
Oxygen  and  nitrogen  form  the  greater  part  of  its 
composition.  The  vapour  of  water,  carbonic  acid  gas, 
and  every  kind  of  emanation  from  the  earth's  surface, 
add  themselves  to  the  two  first-named  gases.  Oxygen 
is  absorbed  by  animals,  and  replaced  by  carbonic 
acid.  The  converse  takes  place  in  vegetation,  and  a 
like  exchange  of  gases  occurs  in  combustion. 

The  vapour  of  water,  raised  by  the  action  of  the 
winds  from  the  vast  oceanic  reservoirs,  floats  above  us 
in  the  form  of  clouds,  and  is  distributed  over  the 
surface  of  the  earth  in  beneficent  showers.  But 
again  the  water  finds  its  way  back  by  means  of 
rivers  and  floods  to  its  original  point  of  departure,  to 
be  again  converted  into  vapour  and  recommence  the 
cycle  of  its  transformations. 

There  is  a  compensating  or  balancing  process 
continually  going  on  among  the  numerous  causes  of 
change,  which  renders  the  composition  of  the  air 
sensibly  constant,  and  makes  its  every  movement 
tend  to  uniformity. 

The  cloud  which  obscures  the  summit  of  a  moun- 
tain marks  the  locality  of  a  very  rapid  movement  of  the 
air.  This  motion  is  caused  by  the  contact  of  a  hot 
and  moist  air  with  one  much  colder.  But  the  wind  bears 


APPARENT  IMMOBILITY.  289 

the  cloud  away,  and  it  dissolves  again,  or  vanishes 
when  the  air  is  dry.  The  apparent  immobility  of  a 
cloud  on  the  top  of  a  mountain  is  caused  by  its  being 
constantly  re-lornied.  Its  variations  are  really  inces- 
sant and  rapid.  They  pass  unobserved  by  us,  and 
thus,  fur  a  long  period  together,  mountain-clouds 
app.^ar  as  if  they  had  settled  down  immutable.  Very 
slow  changes,  as  we  have  remarked  above,  present 
the  a[)pearance  of  unchangeableness,  no  less  than 
very  rapid  ones. 

The  vault  of  heaven  is  thickly  besprent  with  stars, 
the  greater  number  of  which  we  call "  fixed,'*  while  a 
few,  called  "  planets,"  constantly  change  their  places. 
The  fixed  stars,  while  preserving  the  same  relative 
position  unchanged,  seem,  as  a  whole,  to  make  a 
daily  revolution  round  a  point  marked  by  the  polar 
star,  and  the  latter,  or  centre  of  rotation,  does  not  at 
first  sight  appear  to  shift  its  position.  A  long  and 
careful  study  of  the  heavens,  however,  has  shown 
that  this  is  not  the  case.  The  apparent  revolution 
of  the  whole  concave  of  stars  is  accounted  for  by  the 
fact  that  the  earth  moves  on  its  axis,  as  well  as 
describes  an  orbit  round  the  sun.  But  the  stars  are 
at  such  an  enormous  distance  from  us  that  the  axis 
of  our  globe  remains,  practically,  parallel  to  itself 
(luring  the  whole  period  of  the  earth's  annual  revo- 
lution, so  that,  at  any  given  period  of  the  year,  the 

u 


290  THE  BOTTOM  OF  THE  SEA, 

stars  are  seen  in  the  same  places  as  if  the  centre  of 
the  earth  were  a  fixed  position — that  is  to  say,  as  if 
it  always  pointed  to  the  same  spot  in  the  heavens. 
This  constant  parallelism  of  the  earth's  axis  is,  how- 
ever, only  apparent.  In  reality,  it  shifts  to  the 
extent  (taking  the  extreme  limit)  of  4°,  its  revolution 
describing  a  cone  in  about  20,000  years. 

If  the  stars  are  thus  shifted  from  their  apparently 
fixed  position,  their  relative  situation  is  at  least  con- 
stant, you  will  say  ?  Careful  observation,  extended 
over  many  years,  has  shown  the  contrary.  The 
whole  solar  system  is  moving,  as  if  it  were  one  com- 
pact and  independent  organisation,  through  space. 
Astronomers  have  demonstrated  that  it  is  approaching 
the  constellation  Hercules,  but  it  would  require  ages 
of  observation  to  detect  any  variation  in  the  relative 
positions  of  the  fixed  stars.  Such  observation  would 
demonstrate  by  an  extraordinary  effect  of  perspective, 
which  it  is  no  part  of  our  present  business  to  ex- 
plain, that  their  distance  from  Hercules  is  in- 
creasing. 

Every  day  the  sun  rises  above  the  horizon,  and 
fsets  at  the  opposite  extremity  of  the  heavens ;  so  the 
iieat  of  the  day  succeeds  constantly  the  cold  of  the 
night.  Year  after  year  the  ice  is  melted  by  the 
soft  breath  of  the  spring ;  year  after  year  summer 
ripens   the   fruits    of  the   earth.     Year   after  year 


CLIMATE  GRADUALLY  CHANGING.  291 

autumn,  with  its  heats  and  tempests,  despoils  the 
trees  of  their  beautiful  verdure  ;  then,  with  the  same 
regularity  of  succession,  winter  hangs  her  snowy- 
garlands  on  the  branches,  and  strikes  with  sudden 
paralysis  the  mountain  torrent.  The  same  succes- 
sion of  phenomena  appears  to  be  continually  repro- 
duced, with  such  modifications  as  would  sugi^est  a 
capricious  and  ill-regulated  will.  Notwithstanding 
that  apparent  regularity,  within  certain  limits,  the 
climate  of  the  earth  is  undergoing  a  slow  but  con- 
stant variation.  The  debris  of  every  kind  found  in 
the  earth's  crust  affords  demonstrative  proof  that 
the  distribution  of  temperature  on  the  surface  of  the 
globe  has  been  very  different  at  remote  periods  from 
what  it  is  at  present.  The  surface,  beyond  doubt, 
has  been  subject  to  numerous  vicissitudes;  but  at 
least,  you  will  say,  the  centre  of  the  earth  has  re- 
mained unchangeably  the  same. 

This,  however,  cannot  *  be  the  case ;  for,  as  the 
earth  has  grown  gradually  cooler,  its  crust  has  in- 
creased ill  thickness  and  solidity.  The  contraction 
towards  the  centre  has  been  the  cause  of  breakages 
and  crumplings  in  the  earth's  crust,  and,  consequently, 
of  the  upheaval  of  mountains  and  continents,  the 
sinking  of  the  surface  to  form  valleys,  and,  generally 
speaking,  of  such  variations  of  the  terrestrial  land- 
scape as  could   only  be  produced   through  a  long 


202  THE  BOTTOM  OF  THE  SEA. 

succession  of  ages.  The  human  race  has  not  existed 
for  a  sufficiently  long  period  to  witness  the  grander 
catastrophes  or  changes  of  what,  nevertheless,  there 
are  palpable  traces  remaining  to  attest  the  reality. 

We  are  the  living  witnesses,  however,  of  changes 
whose  average  rapidity  permits  our  senses  to  follow 
the  phenomena,  while  our  memory  or  our  records 
enables  us  to  compare  with  ease  the  different  phases 
through  which  they  pass.  We  observe  that  the  sea 
changes  its  level  day  after  day,  as  if  it  oscillated 
around  a  fixed  point.  We  are  witnesses  to  the  silting- 
up  of  ports  by  the  action  of  marine  currents ;  to  the 
ravages  of  the  sea  when  it  hurls  its  waves  against  a 
rocky  coast ;  and  to  the  growth  of  the  polypier,  which 
opposes  an  invincible  rampart  of  stone  against  the 
assaults  of  the  ocean,  and  builds  up  islands  from  the 
very  bosom  of  the  waters.  We  see  the  mountains 
crumble  down  under  the  action  of  atmospheric  agen- 
cies ;  the  debris  of  continents  washed  down  by  rivers 
into  the  sea,  to  fill  up  its  abysses ;  the  floating  ice- 
chariots  scattering  the  spoil  of  arctic  lands  over  every 
part  of  their  route  ;  marine  currents  drawing  in  their 
train  whatever  they  encounter,  and  accumulating 
upon  their  borders  immense  deposits  of  vegetable 
and  animal  remains,  as  well  as  of  sand  and  mud. 
We  see  the  foraminiferse,  those  pigmies  of  creation. 


SOLIDIFICATION  OF  THE  EABTH.  293 

obstinately,  and  with  immense  labour,  striving  to 
build  up  every  possible  obstacle  to  navigation ;  while 
volcanoes,  like  malignant  demons,  destroy  the  exist- 
ing basin  of  the  ocean,  or  at  least  are  incessantly 
active  in  modifying  its  level,  or  filling  up  its  hollows 
with  ashes  and  cinders.  With  our  own  eyes  we  are 
witnesses  of  these  and  innumerable  other  agencies  of 
change ;  and,  knowing  the  vastness  of  their  con- 
sequences, we  judge,  in  regard  to  past  effects,  what 
causes  have  been  in  action  from  the  results  they 
have  produced. 

For  this  reason,  the  exploration  of  the  bottom  of 
tlie  sea  is  an  excellent  preparation  to  the  study  of 
the  past  history  of  our  planet,  and  of  its  future  pos- 
sibilities. The  sea  itself  would  not  exist  except  for 
the  fact  that  the  earth  was  originally  a  fiery  mass, 
the  surface  of  whicli  has  become  solidified,  and 
in  the  process  of  coohng  has  allowed  the  aqueous 
vapours  to  condense.  Originally  extended  with  an 
even  surface  over  the  whole  globe,  the  sea  served 
everywhere  as  the  menstruum  of  the  first  solid  pre- 
cipitations. Thenceforth  the  crust  of  the  earth  grew 
in  solidity  and  deptli,  both  from  the  exterior  and  the 
interior — on  the  one  side  by  sedimentation,  on  the 
other  by  solidification. 

The  cooling  process  continued.      The  crust,  too 


294  THE  BOTTOM  OF  THE  SEA. 

large  for  the  kernel  which  it  everywhere  enveloped, 
caved  in,  and  thus  the  first  heaving-up  of  mountainous 
masses  marked  the  end  of  a  geologic  period.  Lands 
rose  above  the  waters,  and  marine  deposits  no  longer 
covered  the  entire  globe.  The  constancy  of  the 
ocean  temperature,  owing  to  the  near  neighbourhood 
of  igneous  matters,  rendered  very  feeble,  or  alto- 
gether prevented,  the  formation  of  marine  currents. 
As  the  equilibrium  gradually  ceased  to  exist  in  the 
liquid  mass,  owing  to  the  constant  growth  and  the 
changes  that  were  taking  place  in  the  earth's  crust, 
ocean- currents  came  into  being. 

The  atmosphere  was,  in  its  turn,  modified  by  con- 
tinual precipitations  and  despoiled  of  its  vapour  of 
water,  which  went  to  elevate  the  level  of  the  seas. 
This  operation  again  brought  into  existence  atmo- 
spheric currents. 

The  crust  of  the  earth  still  continuing  to  cool, 
fresh  collapses  would  take  place,  and  fresh  w  rinklings 
or  foldings  of  the  solid  envelope  already  formed. 
New  mountains  arose  from  the  bosom  of  the  waters, 
new  rendings  of  the  soil  gave  free  passage  to  the 
igneous  matters  in  the  interior,  and  hence  the  great 
extent  to  which  volcanic  matter  is  found  spread  over 
the  surface.  By  this  time  living  creatures  had  ap- 
peared, which  at  first  were  remarkable  for  the  sim- 
plicity of  their  structure  and  for  the  capability  of 


CHANGE  OF  THE  SEASHORES.  205 

the  same  species  to  dwell,  at  the  same  time,  on  any 
part  of  the  earth.  The  currents  of  the  atmosphere 
and  the  ocean  were  more  and  more  decidedly  and 
definitively  established. 

The  extent  of  dry  land  was  continually  increased 
by  fresh  elevations  above  the  waters.  Kivers  and 
lakes  were  formed ;  in  addition  to  the  hitherto  ex- 
clusively marine  deposits  were  those  of  the  fresh 
waters  and  salt  pools.  Plants  growing  in  marshes 
or  on  dry  lands  extended  their  species  over  new  con- 
tinents. 

As  time  went  on,  the  inequality  of  temperature  at 
different  points  of  the  globe  augmented  ;  the  existing 
mountains  increased  in  height;  new  ones  were  heaved 
up ;  the  fauna  and  the  flora  became  more  localised, 
and  the  marine  and  atmospheric  currents  approached 
insensibly  to  the  condition  in  \>hich  we  find  them. 


2.  The  Shore — Its  apparent  fixity — Traces  of  the  presence  of  the 
Ocean  almost  universal. 


Have  we  yet  reached  fixed  conditions,  so  far  as 
regards  the  earth's  surface  ?  Can  we  be  certain  that 
some  fresh  revolution  of  the  globe  will  not  destroy 
the  edifices  of  which  we  are  so  proud,  and  wrap  in  a 
watery  shroud  the  accumulated  fruits  of  civilisation  ? 
If  we  have  indulged  in  any  illusion,  it  is  only  neces- 


296  THE  BOTTOM  OF  TEE  SEA. 

sary  to  study  with  care  the  phenomena  by  which  we 
are  surrounded  to  dispel  it  for  ever. 

Continual  change  is  going  on  in  the  basins  of 
seas.  These  changes  make,  generally  speaking,  but 
slow  progress,  and  are  therefore  difficult  to  follow ; 
but  little  by  little  they  assume  a  character  of  the 
greatest  importance.  Sometimes,  however,  they  are 
sudden,  and  accompanied  by  phenomena  so  terrible 
as  to  strike  mankind  with  horror,  and  apparently  to 
disturb  the  harmony  of  the  universe. 

How  shall  we  demonstrate  the  truth  ot  our  state- 
ment, that  the  bed  of  the  Ocean  is  constantly  chang- 
ing ?  What  we  observe  is  that  the  sea  rushes 
furiously  against  the  shore,  and  throws  its  foam  over 
the  highest  rocks.  As  the  waves  roll  in,  it  would 
almost  seem  as  if  nothing  could  oppose  a  barrier  to 
them :  suddenly  they  are  arrested,  and  the  dreaded 
power  expends  itself  by  diffusion,  as  it  were,  in  an 
inoffensive  sheet  of  water.  But  another  wave  follows 
the  first.  A  third  presses  on,  and  almost  overleaps 
the  former  two.  Nevertheless  each  succeeding  column 
of  the  invading  army  is  vanquished  at  the  same 
point ;  in  a  word,  the  sea  has  encountered  its  shore. 

Thus,  day  after  day,  the  ocean  seems  to  hurl 
defiance  against  the  earth ;  and  if  it  retires,  it  is  to 
renew  the  assault  against  the  barriers  which  it  seems 
resolved  to  break  through,  with  redoubled  strenofth. 


CHANGES  STILL  IN  PltOGBESS.  207 

Twice  every  day  it  advances,  and  covers  with,  its 
waters  the  vast  extent  of  its  coasts ;  twice  it  retires, 
abandoning  to  men  some  of  its  spoils  and  treasures. 
Kestrained  by  a  powerful  though  invisible  hand,  it 
apparently  yields  to  the  obstacle  which  opposes  its 
advance.  Its  movement  is  so  regular  that  we  can 
determine,  for  eveiy  point  of  our  coasts,  the  exact 
times  of  high  and  low  water. 

Thus  regarded,  the  shore  of  the  ocean  would  appear 
to  be  the  very  type  of  unchangeableness.  The  sea 
cannot  pass  it ;  in  our  confidence  we  cultivate  lands, 
build  cities,  construct  ports  and  harbours,  and  throw 
out  piers,  as  if  we  dared  the  sea  to  do  its  worst.  If 
we  would  know  how  puny  oar  best  efforts  are,  let  us 
note  the  fact  that  marine  shells,  the  fossil  lemains  of 
fish,  and  other  evidences  of  the  presence  of  the  ocean, 
are  found  on  the  highest  mountains.  This  debris  of 
former  ages  has  been  converted  into  stone,  and  now 
exists  in  gigantic  masses.  It  is  impossible  to  say  how 
many  ages  may  have  elapsed  since  they  were  living 
beings  :  history  and  human  tradition  take  no  account 
of  them. 

Are  we  to  imagine  that  those  remote  ages  were 
visited  by  the  most  frightful  of  all  catastrophes,  and 
that  we,  more  privileged,  are  exempt  from  similar 
changes  and  their  attendant  dangers  ?  No ;  the 
8upieme  Intelligence  which   governs   the   universe 


298  THE  BOTTOM  OF  THE  SEA, 

has  regulated  the  working  of  its  stupendous  me- 
chanism. Everything  occurs  at  the  regulated  time. 
Nothing  is  left  to  chance.  The  sea  has  once  covered 
the  whole  earth.  Geology  affords  the  data  by  which 
we  may  determine  its  limits  at  successive  epochs. 
But  it  is  not  necessary  even  to  revert  to  remote 
geological  periods  in  order  to  be  convinced  of  the 
fact  that  land  and  sea  have  frequently  changed  their 
relative  level. 


3.  Progressive  enlargement  of  the  Straits  of  Gibraltar  during  the 
Historic  Period — Columns  of  the  ancient  Temple  of  Hercules 
submerged  —  Descriptions  left  by  Avienus,  Pliny,  and  Pom- 
ponius  —  Mellaria,  Carteia,  and  Belon  submerged  —  Other 
examples  of  Cities  and  Islands  covered  by  the  Waters,  and  of 
Mountains  violently  separated  from  Continents. 


The  Straits  of  Gibraltar  is  a  conquest  of  the  ocean. 
Dureau  de  la  Malle  quotes  the  measurements  of  old 
geographers,  and  they  tend  to  show  that  it  has  been 
continually  enlarged  even  down  to  our  own  times. 

Avienus  quotes  a  measurement  on  the  authority  of 
Daemon  d'Amphipolis.  It  is  nearly  three  miles,  or 
more  accurately  4694  English  yards.  He  cites  a 
subsequent  measurement  of  nearly  four  miles,  or 
6000  yards,  made  by  the  Athenian  Euctemon. 

Scyranus  of  Ohio,  in  the  year  143  B.C.,  found  it 
measured  nearly  24,000  yards,  or  about  thirteen  miles 


STRAITS  OF  OIBRALTAU.  299 

on  the  side  of  the  Atlantic,  while  at  the  presnt  time 
it  18  double  that  distance  between  Spartel  and  Tra- 
falgar. 

Turanius  Gracilis,  who  was  born  on  the  shores  of 
the  strait  100  years  B.C.,  gives  the  width  from  Mel- 
laria,  in  Spain,  to  Cape  Blanco,  on  the  African  side, 
as  about  foui  -i^nd-a-half  miles,  or,  more  accurately, 
7800  yards. 

Strabo  estimates  the  greatest  breadth  at  nearly 
seven  miles,  or  about  12,000  yards. 

Pliny,  who  had  been  quaestor  in  Spain,  and  had 
visited  the  strait,  gives  about  seven-and-a-half  miles 
for  the  narrowest  part,  and  about  ten  miles  for  the 
widest. 

Bishop  Victor,  about  a.d.  500,  found  the  distance 
about  twelve  miles ;  the  Spanish  measurement  at  pre- 
sent is  fourteen  miles. 

These  various  estimates  are  good  evidence  that  the 
strait  has  been  gra  lually  enlarged  from  remote  times 
to  the  present.  Besides  this,  Avienus  relates  that 
between  Africa  and  Europe  there  were  two  wooded 
isles,  on  which  were  built  a  temple  and  altars  in 
honour  of  Hercules.  These  were  called  the  Pillars  of 
Hercules.  The  same  author  mentions  that  the  Car- 
thaginians were  obliged  to  build  flat-bottomed  vessels 
to  sail  over  the  shallow  water.  Finally,  he  says,  we 
know  that  Hannibal  reports  that  there  was  a  bottom- 


300 


THE  BOTTOM  OF  THE  SEA, 


less  and  boundless  sea  farther  to  the  west — a  proof 
that  what  he  says  about  the  Straits  of  Hercules  may 
ba  regarded  as  trustworthy. 

Pliny,  who  visited  the  straits,  speaks  of  a  low-lying 
island,  covered  with  wild  olives,  situate  in  mid  chan- 
nel, upon  which  was  built  the  Temple  of  Hercules. 
Pomponius  Mela,  a  Spaniard,  to  whom  these  parts 


Greatest  breadth  about  g  miles 


-lOOOyrfj 


Fig.  58. — Straits  of  Gibraltar. 

1.  View  and  Section  in  the  time  of  Pliny. 

2.  Section  of  the  existing  Charts. 

were  familiar,  pictures  the  strait  as  a  channel  broken 
by  a  number  of  small  islands  without  names.  In  our 
day  the  largest  ships  sail  freely  over  these  waters. 

In  1748,  on  the  occasion  of  a  very  low  tide,  the 
remains  of  the  famous  Temple  of  Flercules  were  dis- 
covered in  the  oceanic  part  of  the  strait,  and  some 
souvenirs  of  it  were  obtained  for  preservation. 

Jean  Conduit,  as  related  by  Signer  Ignacio  Lopez  de 


SUBMERGED  CITIES.  301 

Ayla,in  his  '*  History  of  Gibraltar,"  assures  us  that  the 
sea  covers  the  greater  part  of  the  land  on  which  stood 
the  ancient  city  of  Melhiria.  Even  in  the  Bay  ol* 
Gibraltar  the  sea  has  engulfed  a  part  of  Carteia,  or 
Algesiras.  Three  leagues  to  the  west  of  Tarifa,  the 
city  of  Belon  occui)ied  the  shore  of  the  strait.  It  is 
now  engulfed,  and  we  find  traces  of  its  existence 
beneath  the  waves. 

Colonel  James,  in  his  "  History  of  the  Straits 
of  Hercules,"  mentions  that  during  an  earthquake, 
some  ages  ago,  the  Isle  of  Gales  disappeared,  together 
with  the  small  islands  opposite  the  city  of  Bactes, 
near  Tarifa,  and  a  rock  named  La  Perle,  which  was 
once  an  island,  and  is  now  covered  with  more  than 
twelve  feet  of  water  at  low-tide.  The  same  author 
speaks  of  violent  shocks  of  earthquake,  which,  in  the 
year  246  B.C.,  overthrew  the  last  remaining  part  of 
the  Isle  of  Cadiz,  and  left  it  completely  covered  by 
the  sea. 

The  earthquake  of  1755,  which  destroyed  the  city 
of  Lisbon,  and  was  felt  far  and  wide,  was  not,  says 
Colonel  James,  to  be  compared  for  the  violence  of  its 
effects  with  that  which  engulfed  Gales,  which  was 
of  many  leagues  in  extent.  Nevertheless,  it  was 
plainly  felt  at  Gibraltar,  where  Colonel  James  himself 
was  an  observer  of  the  phenomenon. 

()n  the  morning  of  the  1st  of  November,  1755,  a 


802  THE  BOTTOM  OF  THE  SEA. 

shock  was  felt  which  histe  I  half  a  minute.  It  com- 
menced by  a  trembling  of  the  earth,  then  a  violent 
shock  succeeded,  which  was  followed  by  a  trembling 
similar  to  that  with  which  the  earthquake  commenced, 
and  which  gradually  diminished.  The  sea  rose  more 
than  three  yards  above  its  ordinary  level,  and  then 
sank,  leaving  dry  upon  the  shore  many  fish,  and  all 
tliat  it  had  at  first  engulfed. 

We  may  add  to  the  list  of  cities  that  have  been 
lost  those  of  Helice  and  Bnra,  in  Achaia,  which  were 
submerged  in  the  year  3(58  B.C.  The  greater  part  of 
Lycadia  was  also  covered  by  the  waters. 

Strabo,  in  his  Egyptian  voyage,  relates  that  he 
saw  Mount  Casius,  which  had  been  suddenly  sepa- 
rated from  the  continent  and  become  an  island,  which 
it  was  necessary  to  sail  round  to  reach  Phoenicia. 

Sorca,  one  of  the  Moluccas,  was  swallowed  up  by  the 
sea  during  an  earthquake  in  1693. 

At  Java  a  mountain,  three  leagues  in  circum- 
ference, disappeared  suddenly  in  1772. 

It  is  on  record  that  a  space  of  about  sixty  leagues, 
in  the  province  of  Chan-tsy,  in  China,  was  completely 
<  overed  with  water  in  a  few  days,  in  1566. 

St.  Lawrence  once  joined  the  American  continent, 
\  ut  is  now  separated  from  it  by  an  arm  of  the  sea, 
some  hundreds  of  yards  broad. 

One  of  the  most  disastrous  eruptions  ut'  tlie  sea  *ji\ 


DISASTERS  IN  ZKA  LAND. 


303 


record  is  that  which,  in  1440,  submerged  more  than 
two  hundred  cities  of  Friesland  and  Zealand.  For  a 
long  time  after  this  catastrophe,  the  summits  of  the 


Fig.  59. — Irruption  of  the  Sea  in  Zealand. 

towns  and  the  points  of  the  steeples  could  be  seen 
standing  above  the  surface  of  the  sea. 

We  might  multiply  these  examples  of  the  fact  that 
the  bottom  of  the  sea  is  continually  chauiriiii::.     Here 


304  THE  BOTTOM  OF  THE  SEA. 

cities,  nay  entire  continents,  are  covered  by  the 
waters :  there,  on  the  other  liand,  the  land  has  been 
known  to  rise,  as  in  the  case  of  the  island  of  Julia,  and 
in  that  of  the  Azores,  and  the  Archipelago  of  Santorin. 
The  port  of  Aigues  Mortes  has  now  three  leagues  of 
shore.  The  ruined  Temple  of  Serapis,  at  Pozzuoli,  was 
for  a  long  time  engulfed  ;  it  is  now  uncovered  again. 
In  the  north  of  Sweden  the  sea  appears  to  be  retiring, 
whilst  it  slowly  invades  the  south  of  that  country,  and 
at  no  very  distant  period  it  was  the  cause  of  great 
destruction  by  its  inroads  in  Pomerania. 


4.  The  Quantity  of  Water  which  covers  the  Earth  is  sensibly  con- 
stant— An  Elevation  in  one  point  is  balanced  by  a  corre- 
sponding Subsidence  in  another  —  Aristotle's  opinion  about 
the  Greek  tradition  of  the  Deluge — The  Earth  will  become 
dryer  and  colder. 

If  the  sea  retires  from  a  given  pLice,  another  be- 
comes submerged.  We  are,  therefore,  led  to  con- 
clude that  the  water  area  varies  but  little  over  the 
whole  of  the  earth's  surface,  but  that  the  bed  in 
which  it  rests  is  ceaselessly  modified. 

Such,  moreover,  was  Aristotle's  opinion.  He  be- 
lieved that  the  apparent  changes  in  the  level  of  the 
sea  in  any  given  spo^  could  not  be  explained  by  the 
supposition  that  the  seas  were  drying  up,  as  certain 
philosophers   of    his   time    had   imagined.     In   the 


OPINION  OF  AEISTOTLK.  805 

words  of  this  illustrious  savan  :  *•  Ouly  those  of  narrow 
riews  and  small  experience  attribute  these  partial 
changes  to  an  overthrowing  of  the  whole  globe. 
When,  in  support  of  their  views,  they  bring  forward 
the  drying-up  of  seas,  and  the  existence  of  dry  land 
where  it  formerly  was  not,  they  give  authentic  facts, 
from  which,  however,  they  deduce  false  conclusions. 
It  is  true  that  certain  spots  Iieretofore  covered  with 
water  now  form  a  portion  of  the  continent,  but 
the  contrary  is  also  the  case,  and  any  one  who 
studiously  examines  the  facts  would  find  that  the 
sea  had  invaded  and  submerged  several  parts.  Such 
appears  to  be  the  explanation  of  Deucalion's  flood, 
the  ravages  of  which  were  more  especially  felt  in 
Greece,  and  which  among  other  provinces  was  most 
terribly  felt  in  ancient  Helas,  a  country  extending 
from  Do^lona  to  the  Achelous.  This  river  then 
changed  its  course  several  times.  The  province  was 
at  that  time  inhabited  by  the  Selles,  and  by  the 
people  named  Greeks,  now  called  Hellenes." 

Certain  coasts  of  the  same  sea  will,  in  the  same 
time,  show  but  little  variation.  The  Strait  of 
Messina,  more  especially  on  the  Sicilian  side,  re- 
ceives quantities  of  sand;  but  it  lias  relatively  suffered 
such  slight  changes,  that  the  same  race  have  in- 
habited it  since  the  time  of  Homer.  In  reading  the 
descriptions  given  of  this  place  by  Homer,  Polybius, 


306  THE  BOTTOM  OF  THE  SEA. 

and  Spallanzani,  it  is  surprising  to  find  that  authors 
living  in  times  so  far  apart  give  similar  details 
respecting  the  inhabitants  in  this  arm  of  the  sea.* 
Now  we  have  seen  that  marine  animals  sometime « 
emigrate,  and  leave  their  haunts  to  other  species,  if 
the  depth  changes  notably.  Swordfish  are  now  still 
caught  in  the  manner  described  by  Polybius. 

Sometimes  the  movements  of  the  terrestrial  crust 
are  limited  to  a  very  small  range  of  country — some- 
times they  embrace  a  very  large  extent.  They  are 
nearly  always  compensated  by  inverse  movemeuts, 
produced  at  more  or  less  distant  points.     The  gra  lual 

*  Polybius  wrote,  two  thousand  years  ago  :  "  The  swordfish,  sea- 
dogs,  and  other  cetaceous  animals,  become  singularly  fat  every  year 
by  living  on  the  tunny-fish,  which  visit  the  coast  of  Italy  in  shoals^ 
and  which  their  enemies  watch  for  in  the  straits.  In  fishing  two 
men  are  attached  to  each  boat — one  sculling,  and  the  other  stancUng 
at  the  prow  armed  with  a  spear.  The  various  boats  have  a  common 
scout,  in  an  elevated  situation,  who  signalises  the  approach  of  the 
swordfish,  for  the  fish  swims  with  half  his  body  out  of  the  water. 
When  it  approaches  the  boat  the  spearman  strikes  it  with  his  spear, 
the  head  of  which  carries  a  barb,  loosely  fixed,  so  that  it  can  be  easily 
detached  when  the  spearman  withdraws  the  handle.  To  tlie  iron 
head  of  the  lance  is  fastened  a  long  cord,  which  is  let  out  to  the 
wounded  fish,  until  by  his  continued  struggles  to  escape  he  shall 
have  lost  all  his  strength.  Then  they  haul  it  ashore,  or,  if  not, 
take  it  on  board  their  boat.  If  the  spear-handle  fall  into  the  sea,  it 
is  not  necessarily  lost;  it  is  made  of  oak  and  spruce,  in  such  a 
manner  that  the  oak  sinking  on  account  of  its  greater  weight 
permits  the  spruce  to  project  above  the  surface  of  the  water,  so  that 
the  fisherman  may  easily  see  and  regain  it.  Sometimes  it  happens 
tliat  the  rower  is  wounded,  the  swordfish  being  armed  with  a  L-ng 
bwoid,  anil  being  as  furious  and  impetuous  as  a  boar." 


FUTURE  OF  THE  EARTH.  307 

cooling  of  our  planet  causes  the  thin  crust  already 
foruiel,  by  unequal  contraction,  to  pucker  up.  The 
sea  occupies  the  cavities — tlie  prominences  alone 
appear  above  the  waters. 

Water  tends  to  combine  more  and  more  with  the 
rocks.  A  time  will  probably  come  when  the  earth 
will  be  too  cold  for  water  to  exist  in  the  liquid  state. 
It  is  to  be  understood,  in  fact,  that  the  quantity  of 
water  which  bathes  our  planet  continually  diminishes  ; 
but  this  diminution  is  so  slow,  that  thousands  ot* 
years  are  not  sufficient  to  make  it  evident. 


808  THE  BOTTOM  OF  THE  SEA. 


SUDDEN  MOVEMKNTS  OF  THE  SUBiMAKINE  SOIL. 


1.  Earlh(i\ialces  modify  the  Bed  of  the  Ocean — Submarine 
Volcanoes. 

The  bottom  of  the  sea,  as  well  as  the  surface  on 
which  we  live,  is  subject  to  modifications  by  the 
action  of  earthquakes.  They  are,  generally,  accom- 
panied by  submarine  volcanoes,  which  also  alter  the 
sea-be  1,  and  cause  a  displacement  of  the  waters.  It 
is  observable,  in  fact,  that  volcanoes  never  display 
their  whole  energy  except  in  the  neighbourhood  of 
seas  or  large  sheets  of  water.  The  existence  of  sub- 
marine volcanoes  need  not  then  excite  astonishment ; 
it  is  probable,  indeed,  that  their  number  is  very 
great,  and  it  is  reasonable  to  attribute  to  the  action 
of  submarine  eruptions  of  which  we  have  no  know- 
ledge, the  seismical  phenomena  that  have  been  ac- 
companied by  no  visible  volcanic  disturbances. 

At  the  commencement  of  its  activity,  subma- 
rine volcanic  action  is  sometimes  signalised  by  a 
peculiar    agitation  of  the  sea,  where  the  depth  is  at 


8VBMARINE  VOLCANOES, 


309 


all  considerable.  If  the  depth  be  slight,  or  the 
activity  of  the  volcano  very  great,  the  water  bubbles ; 
a  column  of  smoke  rises  above  the  level  of  the 
sea ;  flames,  scoria?,  or  incandescent  st(jnes  demon- 
strate the  presence  of  a  volcano.  The  sea  changes 
colour  to  a  greater  or  less  extent,  and  becomes  warm. 
Ships  receive  a  shock  as  if  they  had  struck  a  rock ; 
indeed,  in  some  cases  the  ooucussion  is  so  violent 
that  vessels  have  lost  their  masts. 

Volcanic    products  of  every  kind,   however,   ac- 
cumulate at  the  bottom  of  the  sea,  covering  every 


rr.  C 


Fig.  60. — Eruption  of  a  Submarine  Volcano. 

living  thing ;  streams  of  lava,  masses  of  scoriae,  and 
rocks,  contribute  to  an  elevation  of  the  soil  which 
must  eventually  raise  it  to  the  light  of  day.  Such 
is  often  the  origin  of  volcanic  islands. 

Submarine  earthquakes  disturb  the  sea  through- 
out its  whole   depth,  causing  the  terrible  waves  of 


310  THE  BOTTOM  OF  THE  SEA. 

which  we  have  spoken  in  a  previous  chapter.  The 
facts  we  are  about  to  relate  will  exhibit  the  great 
influence  exerted  by  subterranean  fires  over  the  sub- 
marine regions  of  the  whole  globe. 


2.  Greek  Archipelago  —  Delos  and  Rhodes  upheaved  from  the 
Bottom  of  the  Sea — Successive  additions  to  the  Archipelago  of 
Santorin. 

The  existence  of  submarine  volcanoes  has  long 
been  known.  Several  are  to  be  found  in .  Greece. 
The  islands  which  have  appeared  from  time  to  time, 
as  if  by  enchantment,  have  owed  their  birth  to  vol- 
canic causes.  Ancient  writers  make  mention  of 
certain  phenomena  of  this  kind;  but  their  state- 
ments, being  founded  for  the  most  part  on  inexact 
information,  or  on  more  or  less  uncertain  traditions, 
can  be  of  little  utility  from  a  scientific  or  even  his- 
torical point  of  view. 

"The  celebrated  islands  of  Delos  and  Khodes," 
says  Pliny  (Liv.  II.  chaps,  xviii.  and  xix.),  *'  have, 
from  all  accounts,  risen  from  the  waters :  moreover, 
smaller  ones  have  been  seen  to  appear — such  as 
Anapte,  beyond  Melos;  Nea,  or  Nova  Insula,  be- 
tween Lemnos  and  the  Hellespont ;  Alone,  between 
Lesbos  and  Theos;  Thera  and  Therasia,  amongst 
the  Cyclades,  in  the  fourth  year  of  the  135th  Olym- 
piad ;  Hiera,  or  Automate,  situated  between  the  two 


NEW  ISLANDS  FORMED.  311 

preceding,  and  formed  130  years  subsequently.  In 
our  time,  110  years  later  than  the  above,  during  the 
consulate  of  M.  Julius  Sihinns  and  L.  Balbus  (yea;- 
19  A.D.)  appeared  Thia." 

Many  other  ancient  authors — among  the  rest 
Justin,  Cassiodorus,  Dion  Cassius,  Plutarch,  Seneca, 
and  Strabo — give  very  circumstantial  details  of  the 
successive  birth  and  growth  of  some  of  these  islands 
by  their  elevation  out  of  the  sea.  But  the  origin 
of  some  of  them  is  surrounded  with  purely  fabu- 
lous circumstances,  and  we  are  obliged  to  leject 
nearly  all  the  ancient  narratives  as  being  but  little 
worthy  of  belief  Volcanic  phenomena  were  not 
seriously  studied,  or  even  carefully  observed,  until 
modern  times. 

One  of  the  most  celebrated  islands  of  the  Grecian 
Archipelago  is  Thera,  subsequently  named  8ante- 
Irene,  and  later,  Santorin.*  Half  a  league  from  this 
island  now  exists  Apronysi,  the  ancient  Therasia.  It 
appeared  for  the  first  time  in  236  B.C.  (the  fourth  year 
of  the  135th  Olympiad,  according  to  Pliny,  cited 
above).  Automate  appeared  130  years  after  (106  B.C.), 
and  was  named  Hiera  in  consequence  of  the  worship 


*  Suntorin  is  an  immense  crateriform  mountain,  some  thirty-six 
miles  in  circumference.  It  may  be  accurately  describe  d  ns  a  furnace 
of  incessant  volcanic  activity,  some  part  of  it  being  almost  con- 
stantly in  eruption.— TiJ. 


312  THE  BOTTOM  OF  THE  SEA. 

of  Vulcan  there  established.  Thia  (4  B.C.)  rose  at 
the  distance  of  about  300  yards  from  Hiera.  The 
details  given  by  the  ancient  geographers,  therefore, 
agree  with  each  other. 

Violent  eruptions  of  cinders,  rocks,  and  lava,  in  a 
state  of  ignition,  filled  the  arm  of  the  sea  which 
separated  Thia  from  Hiera  in  the  year  726  of  our 
era. 

Similar  phenomena  occurred  in  1427,  as  is  at- 
tested by  a  marble  monument  erected  in  Santorin, 
near  Fort  Scauro.  A  new  island,  designated  N ea- 
Kameni  {New  Burnt-island),  appeared  in  1570,  at 
the  termination  of  a  sixth  eruption.  Hiera  was 
then  called  Paloe-Kameni,  which  signifies  Old  Burnt- 
island. 

We  owe  to  Father  Kircher  the  details  of  an  eruption 
which,  in  1650,  threw  these  coasts  into  trouble  during 
a  whole  year.  It  was  accompanied  by  showers 
of  cinders  and  whirlwinds  of  flame,  which  were  seen 
to  issue  from  the  sea.  The  quantity  of  cinders 
thrown  out  was  so  considerable,  that  Smyrna  and 
Constantinople  were  much  inconvenienced. 

A  new  island  was  thrown  up  in  1707.  Mons.  J. 
Girardin  describes  this  phenomenon  in  the  following 
words:  "On  the  23rd  of  May,  1707,  at  sunrise,  a 
floating  rock  was  seen  at  sea  about  a  league  from  the 
shore  of  Santorin.     Some  sailors  took  it  for  a  ship 


NEW  ISLAND  NEAU  SANTOBIN.  3i;i 

about  to  break  up,  and  approaclied  it  with  a  view  to 
pillage.  Arrived  near,  and  seeing  what  it  was,  they 
had  the  courage  to  descend ;  they  brought  back 
some  pumice-stone  and  a  few  oysters  which  were  at- 
tached to  it.  The  rock  was  probably  a  large  mass  of 
pumice,  that  the  agitation  of  the  earth,  which  occurred 
a  little  time  previously,  had  detached  from  the 
bottom  of  the  sea.  After  a  few  days  it  beciune  fixed, 
and  thus  formed  a  little  island,  which  augmented 
in  size  from  day  to  day.  On  the  14t]i  of  June  it 
was  some  800  yards  in  circumference,  and  about 
twenty-four  feet  in  height ;  in  shape  it  was  roundish, 
and  formed  of  a  white  light  earth.  At  this  period 
the  sea  began  to  be  disturbed,  and  the  heat  near  the 
island  was  so  great  as  to  prevent  access  to  it ;  a 
strong  odour  of  sulphur  also  spread  around.  On  the 
16th  of  July  there  appeared  in  close  proximity  to  it 
seventeen  or  eighteen  black  rocks;  on  the  18th,  a 
dense  smoke  was  emitted  by  it  for  the  first  time,  and 
subterranean  rumblings  were  heard.  On  the  19th, 
fire  began  to  be  visible,  and  its  intensity  gradually 
augmented.  At  night-time  the  island  had  the  ap- 
pearance of  a  number  of  furnaces  vomiting  flames. 
Its  volume  increased,  and  the  fumes  became  insup- 
portable at  Santorin.  The  sea  was  now  violently 
agitated,  and  dead  fish  were  thrown  on  the  shore ; 
the  subterranean,  noises  resembled   discharges    of 


314  THE  BOTTOM  OF  THE  SEA. 

artillery ;  the  fire  made  new  openings,  whence  issued 
showers  of  ignited  cinders  and  stones,  which  some- 
times fell  at  a  distance  of  two  leagues.  This  state  of 
things  lasted  a  whole  year.  In  1767,  a  new  eruption 
took  place  between  Nea-Kameni  and  Paloe-Kameni ; 
it  recommenced  in  the  month  of  June,  and  after 
working  ten  or  twelve  days,  a  new  island  rose  up  in 
the  neighbourhood  of  Nca-Kameni.  During  four 
months,  a  series  of  terrible  phenomena  occurred ; 
considerable  portions  of  the  island  were  swallowed  up, 
but  others  were  formed  ;  at  last  a  second  island  ap- 
peared, and  it  united  with  the  first  in  June.  It  was 
named  the  Black  Island,  on  account  of  the  colour  of 
its  soil.  The  subterranean  disturbance  continued 
until  the  end  of  the  following  year;  and  on  the  15th 
of  April,  there  occurred  an  eruption  of  large  ignited 
stones,  which  fell  two  miles  off." 

The  eruptions  and  upheavings  from  the  bottom  of 
the  sea  continued  long  after.  The  Academie  des 
Sciences  sent  M.  Fouqu^  to  study  on  the  spot  the 
manner  in  which  this  remarkable  archipelago  became 
developed.  M.  Fouque  perfectly  distinguished  the  two 
processes  simultaneously  working  towards  the  produc- 
tion of  new  lands — the  raising  of  the  ground,  and  the 
increaseof  the  raised  spots  by  the  deposit  of  lava,  scoria), 
and  rocks,  which  were  cast  out  from  the  boiling  cavern. 

The  bottom  of  the  sea  is,  as  we  have  seen,  gei^erally 


THE  AZORES  VOLCANIC.  315 

colder  than  the  surface,  If,  therefore,  rocks  situated 
at  a  great  depth  are  brouglit  rapiilly  to  the  surface, 
they  will  not  have  time  to  acquire  warmth  in  rising, 
and  will  therefore  cool  the  surrounding  waters  to  a 
certain  distance.  The  lava  and  stones  thrown  out  by 
the  volcano  will,  on  the  contrary,  heat  the  water 
sometimes  almost  to  boiling. 

The  elevation  of  the  island  of  Julia,  to  the  west 
of  Sicily,  was  accompanied  by  phenomena  similar  to 
the  above. 

3.  The  Azores — Appearance  and  Disappenranoe  of  Islands  subse- 
quent to  Earthquakes — The  epliememl  Island  Sabrina. 

The  Azores  are  entirely  volcanic,  and  we  there  find 
the  same  remarkable  phenomena  occurring  that  we 
have  alrea'ly  noticed  in   the  Grecian  Archipelago. 

Evidence  of  the  existence  of  a  submarine  volcano, 
near  St.  Michael,  was  given  by  four  eruptions  in  less 
than  200  years.  One  of  tliem  began  on  the  11th  of 
June,  1(338,  during  an  earthquake.  Flames  an  I 
smoke  were  thrown  out  by  the  agitated  sea  near  St. 
Michael ;  earth  and  rocks  were  projected  to  a  great 
height,  and,  again  falling  into  the  sea,  at  last  ac- 
cumulated sufficiently  to  form  an  island  ten  kilo- 
metres in  extent,  and  nearly  400  feet  high.  Like 
Julia,  the  island  soon  disappeared. 

Another  earthquake  occurred  suddenly  on  the  IMsi 


316 


TEE  BOTTOM  OF  THE  SEA. 


of  December,  1719,  and  an  island  was  formed  between 
Tereeira  and  St.  Michael.  At  first  it  was  of  sufficient 
elevation  to  be  seen  seven  or  eight  leagues  out  at  sea  ; 


Fig.  61. — Submarine  Eruption  at  the  Azores. 

it  vomited  incessantly  a  thick  column  of  smoke,  cin- 
ders, and  pumice ;  a  stream  of  molten  lava  flowed 
down  its  sides,  and  the  sea  became  very  hot  in  its 
neighbourhood.  The  height  of  the  island  diminished 
rapidly;   after  existing  two  years,  in  1722   it  had 


THE  NEW  ISLASD  SABHISA.  317 

^unk  to  the  level  of  the  sea.  It  disiippeared  on  the 
17th  of  November,  1623. 

Violent  earthquakes  disturbed  the  neighbourhood 
of  St.  Michael  during  the  months  of  July  and 
August,  1810.  Shortly  after  (January  Slst,  1811) 
the  eartli  split  on  the  eastern  side  of  the  island, 
near  the  village  of  Ginetas,  a  league  and  a  half  from 
the  seashore.  While  the  sea  boiled  violently,  an 
enormous  quantity  of  water  and  smoke,  mixed  with 
earth  and  cinders,  was  thrown  into  the  air.  Stones 
were  thrown  to  a  height  of  2000  feet.  The  eruption 
lasted  eight  days ;  a  bank  of  pumice  was  then  visible, 
against  which  the  waves  dashed  on  a  spot  where  the 
water  was  previously  not  much  less  than  500  feet  deep. 

An  island  one  or  two  kilometres  in  circumference, 
and  about  300  feet  in  height,  was  the  result  of  a 
new  submarine  eruption  on  the  loth  of  June  in  the 
same  year.  Captain  Til  lard,  commanding  the  Sahrina. 
visited  and  took  possession  of  it  in  the  name  of  the 
English  Government.  He  gave  it  the  name  of  his 
vessel.  Little  by  little  the  island  sank,  and  towards 
the  end  of  Fi^bruary,  1822,  a  little  vapour,  floating 
over  the  surface  of  the  sea,  was  the  only  remaining 
trace  of  its  existence. 

Porto  de  Itheo,  a  vast  hollow  crater  in  which  ships 
found  a  resting-place,  as  well  as  the  island  of  Corvo, 
are  of  similar  origin. 


818  THE  BOTTOM  OF  THE  SEA. 

During  a  groat  eartliquake  which,  in  1757,  de 
stroyed  one-seventh  (1500  persons)  of  the  population 
of  the  ishmd    of   St.   George,  eighteen    islets    sud- 
denly appeared   about   600   yards   from   the   shore. 
Th(-ir  fate  was  similar  to  that  of  Sabrina. 

4.  Submarine  Volcano  in  the  Middle  of  the  Atlantic. 

One  of  the  most  remarkable  of  submarine  vol- 
canoes exists  in  the  mildle  of  the  Atlantic  Ocean. 
M.  Daussy  had  already  pointed  out  a  region,  situated 
about  24°  42'  W.  longitude  and  0°  50'  S.  latitude,  as 
interesting  on  account  of  volcanic  phenomena.  We 
reproduce  a  list  ghen  by  M.  Yezian  of  incidents 
observed  on  this  spot,  since  the  mid  He  of  the  last 
century,  by  a  large  number  of  sailors  : — 

1747.  The  ship  Prince,  b  aind  for  tl.e  Indies ;  two  shocks,  as 
though  the  vessel  had  toucht  d  giound. 

1754.  The  ship  Silhouette;  extiaoidinary  shock. 

1758.  Le  Fidele ;  shock. 

1761.   Le  VaiUant ;  an  island  of  sand  observed. 

1771.  The  frigate  Fadfique;  very  violent  shock,  sea  mucli  agi- 
tated. 

180(J.  M.  de  Krusenstern  saw  a  volume  of  smoke  rising,  twice 
repeated,  to  a  gr^  at  height. 

1816.  The  Triton;  a  rock  ti.ree  miles  long  and  one  mile  wide.  2G 
fathoms  of  water ;  bottom,  brown  tand. 

1831.  L'Aigle;  ca'm  sea,  shock,  rumbling  sound  bene.ith  the 
water, 

1832.  La  Seine ;  shocks. 

IhSS.  La  Couronne ;  sciaped  tlie  bottom  with  her  keel;  sounded 
afterward  ,  B.t  fathoms. 


VOLCANO  JN  THE  ATLANTfC.  819 

183G.  Le  Philanthrope ;  shocks  which  lasted  three  minutes,  and 
which  were  also  felt  two  mih  s  off  by  another  vessel 

1836.  S(»me  voleanic  cinders,  collected  near  this  point  wl.ilst  the 
earth  was  in  violent  agitation,  were  forwarded  to  Cakutta. 

1856.  Regina  Cceli ;  rumbling  sound  as  of  a  distant  otorm;  after- 
wards severe  s-hocks,  accompanied  by  a  noise  similar  to  that  produced 
by  striking  several  sheets  of  metal  to<>:t  ther.  The  lielmsnian  wns 
incapable  of  managing  the  tiller,  which  was  dragged  Ironi  Lis 
hands. 

1856.  On  the  tame  day  and  at  the  s:ime  hour— i.e.,  on  the  3Uth  of 
December,  at  4  o'clock  in  the  morn  ng — the  ship  Godavery  received 
a  severe  shock  at  a  slight  distance  from  the  Regina  Cmli. 

18(51.  February  20.  Submarine  earthquake  felt  on  board  the 
F^licie,  wl  ic.i  lasted  a  minute,  and  was  preceded  by  a  noise  coming 
from  the  westward. 


5.  Submarine  Eruptions  near  Kamtschatka— Iceland — Ignited  Sea; 
appearance  of  an  Island  near  IteikianesfS— Kise  of  a  Fiery  Islajul 
from  the  Ocean,  near  the  Aleutian  Isles. 

Occurrences  similar  to  the  above  have  often  been 
observed  near  Kamtschatka,  and  in  the  latitudes  of 
Russian  America.  For  example,  an  eruption  occurred 
on  the  10th  of  May,  1814,  when  an  island  rose  above 
the  water,  vomiting  bitumen  through  many  tissures. 

Captain  Kotzebue  was  eyewitness  to  the  birth  of 
t*n  island  near  Ounimack,  in  the  Aleutian  Archi- 
pelago. An  account  of  the  circumstances  will  be 
found  in  the  narrative  of  his  voyage. 

On  the  7th  of  May,  1796,  M.  Krinckhoff,  agent  of 
the  Kussian  American  Company,  was  at  tlie  north- 
west £X)int  of  Ounimajjk  ;  a  tempe&t,  which  blew  from 


320  THE  BOTTOM  OF  THE  SEA. 

the  north-west  quarter,  prevented  him  from  seeing 
anything  out  at  sea.  On  the  8th,  the  weather 
cleared,  when  he  observed,  at  some  miles  from  the 
shore,  a  column  of  smoke  or  mist  rising  from  the  sea, 
and  as  evening  approached  he  saw  something  black 
upheaved  above  the  smoke.     Durhig  the  night  Hre 


Fig.  62. — Rise  of  a  new  Island  near  Ouuimacii. 

was  emitted  at  the  same  place,  and  with  such  intensity, 
that  at  a  distance  of  ten  miles  objects  were  perfectly 
distinguishable.  Then  a  trembling  of  the  earth,  ac- 
companied by  a  frightful   noise,  which  was  echoed 


ICELAND.  321 

from  the  mountains  of  the  south,  shook  the  entire 
soil.  The  nascent  island  belched  forth  stones,  wliich 
fell  even  upon  Ounimack.  The  earthquake  ceased 
at  suurise,  the  fire  diminished,  and  the  new  island 
appeared  plainly  visible,  conical  in  sliape,  and  of  a 
black  colour. 

A  month  later,  ]\[.  Krinckhofif  saw  it  again.  The 
island  was  higher  than  before,  and  during  all  this 
time  it  had  not  ceased  to  vomit  fire.  Afterwards  it 
appeared  to  increase  in  circumference  and  height, 
but  the  fire  continued  to  diminish.  Generally  it 
emitted  only  vapour  and  smoke,  and  at  the  end  of 
four  years  this  phenomenon  ceased  also.  When,  about 
eight  years  subsequently,  the  island  was  visited  by  a 
company  of  trappers,  the  surrounding  water  was 
found  to  be  of  a  very  high  temperature,  an'l  the  soil 
80  hot  in  many  places  tliat  it  was  impossible  to 
walk  on  it.  Its  circumference,  which  had  gone  on 
augmenting,  was  estimated  at  about  two-and-a-half 
miles,  and  its  height  at  about  350  feet.  The  bottom 
of  the  sea  was  strewn  with  stones  even  to  a  distance 
of  three  miles.  The  hottest  part  of  the  soil  was  from 
about  the  middle  of  the  height  to  the  summit,  and 
the  vapour  which  ascended  from  the  crater  was 
found  to  be  of  an  agreeable  odour. 

Iceland  is  a  very  furnace  of  volcanic  activity,  and 
we  observe  in  its  neighbourhood  phenomena  of  eleva- 

T 


322  THE  BOTTOM  OF  THE  SEA. 

lion  analagous  to  the  instances  we  have  aheady  cited 
Mackenzie  relates  that,  in  the  year  1780,  he  obsersred 
on  the  western  coast  of  the  island,  at  the  distance  oi 
ten  leagues  from  Reikianess,  flames  rising  from  the 
sea  during  many  months.  Afterwards  a  little  island 
made  its  appearance.  For  some  time  this  island 
vomited  flames  and  stones,  and  then  disappeared 
again.  Immediately  afterwards  the  Skaptaa  lokull, 
a  neighbouring  volcano,  broke  out  in  eruption. 


6.  The  Bottom  of  tlie  Sea  feels  the  counterblow  of  turrestrial 
Volcanic  Phenomena, 

Terrestrial  volcanoes  and  earthquakes  are  nearly 
always  re-echoed,  so  to  speak,  from  the  bottom  of  the 
sea.  .  Ships  experience  a  shock  as  if  they  had  passed 
over  a  centre  of  volcanic  activity. 

Cracatoa,  an  island  in  the  Indian  Ocean,  was  de- 
stroyed in  1680  by  an  earthquake.  Vessels  at  sea 
felt  the  shock. 

Gounung-Api,  or  Gounapi,  a  volcano  in  the  Mo- 
lucca group  of  islands,  burst  into  eruption  on  tlie  22nd 
of  November,  1694.  Its  summit  vomite  I  flames  with 
a  great  noise.  The  bottom  of  the  sea  was,  at  the 
same  time,  heaved  up  to  the  level  of  the  soil  of  the 
island,  and  flames  ascended  from  the  waters. 

In  1820,  in  a  bay  situated  to  the  west  of  Gounapi, 


L'BUrTION  OF  TOMBOHO.  a23 

r.nd  where  at  other  times  sixty  fathoms  were  sounded, 
a  promontory  was  formed,  which  increased  in  extent 
until  it  filled  up  the  bay.  it  is  composed  of  gigantic 
blocks  of  basalt  highly  calcined.  The  phenomenon 
was  attended  with  so  little  noise  that  the  inhabitants 


Fig.  63.— Eruption  of  Tombm-o  in  1821. 

of  the  Banda  (or  Nutmeg)  Islands  were  unaware  of  th<; 
occurrence  until  it  was  perfectly  accomplished.  Th^ 
upheaval  was  slow,  accompanied  by  an  extraordinary 
rise  of  temperature  in  the  water,  whieli  biibble<l  np 
in  the  I  ay. 


;i24  THE  J30T1VM  OF  THE  SEA. 

In  the  island  of  Bima,  or  8umbawa,  there  is  a  very 
active  volcano,  named  the  Tomboro.  In  1821  such 
a  movement  of  the  sea  occurred  here,  that  the  island 
was  partly  submerged,  and  vessels  at  anchor  in  the 
port  were  thrown  to  a  great  distance  on  the  shore. 
Many  were  landed  even  on  the  roofs  of  tlie  houses. 
Tomboro  itself  remained  calm  during  the  time,  but  a 
vol(!anic  mountain  to  the  north-east  of  it  threw  up 
stones  and  cinders  in  the  midst  of  a  torrent  of  vapours. 
The  earthquake  was  felt  in  the  neighbouring  isles,  at 
Celebes,  and  even  at  Macassar,  where  the  same  de- 
vastation occurred  as  at  Bima.  These  two  places 
are  nevertheless  separated  by  an  arm  of  the  sea  100 
leagues  broad. 


/.  Products  of  Submarine  Volcanoes — How  they  differ  from  the 
products  of  Subuerial  Volcanoes. 

A  very  close  analogy  has  been  observed  between 
the  products  of  all  the  volcanoes  on  the  earth's  sur- 
face. Submarine  volcanoes  are  no  exception  to  the 
general  rule.  One  and  the  same  cause  produces  all 
these  phenomena.  The  nature  of  the  medium  into 
which  they  eject  their  gas  and  igneous  matter  can 
alone  occasion  any  difference  in  the  character  of  the 
eruption. 

Submarine  lava-streams  may  be  expected  to  cover 


SUBMAEINE  LAVA.  325 

a  great  extent  of  the  ocean-bed,  according  to  the 
opinion  of  Mr.  Poulett  Scrope,  who  has  expressed  him- 
self to  the  following  effect  in  his  work  on  "Geology 
and  the  Extinct  Volcanoes  ot*  Central  France."  "  We 
ought  to  observe,"  he  says,  "  that  lava-streams  at  the 
bottom  of  the  sea  must  have  a  greater  breadth,  com- 
pared with  their  thickness,  than  those  which  are  cooled 
under  atmospheric  pressure,  and  that  this  lateral  ex- 
tension is  proportioned  to  the  depth  of  the  water." 

It  ought  also  to  be  observed  that  lava-streams 
which  have  cooled  at  great  depths  under  the  v\ater 
present  little  scoriae.  This,  in  fact,  has  been  observed 
in  the  old  volcanic  rocks  of  submarine  origin.  This, 
however,  may  be  caused  by  the  influence  of  ocean- 
currents,  or  other  movements  of  the  water." 

Some  knowledge  of  the  peculiar  action  of  submarine 
volcanoes  might  be  acquired  by  investigating  their 
products,  which  may  be  brought  to  light  by  the  sub- 
sequent elevation  of  the  ocean-bed  above  the  level  of 
the  sea.  Examples  of  this  are  frequent  in  the  coral 
isles  of  the  Pacific.  The  basaltic  columns  of  the  south 
and  north  coasts  of  Ireland,  of  the  Faroe  Isles,  of  the 
north-east  of  Teneriffe,  and  numerous  other  localities, 
tend  to  demonstrate  that  the  phenomena  displayed 
by  lava,  when  it  is  ejected  beneath  the  sea,  are  very 
nearly  similar  to  what  occurs  on  the  solid  earth.  The 
principal  differences  seem  to  be : 


326  THE  BOTTOM  OF  THE  SEA. 

1.  That  the  lava  cools  more  uniformly,  and  extends 
(urther  upon  a  plane  surface. 

2.  That  a  submarine  volcano  ejects  a  less  quantity 
of  conglomerate,  or  of  fragmentary  matter,  than  a 
subaerial  one,  or  that  its  igneous  product  extends 
further,  and  stratifies  in  thinner  sheets  of  con- 
temporary lava,  than  is  the  case  with  that  of  other 
volcanoes. 

If  these  opinions  be  correct,  the  regions  where 
we  find  immense  formations,  sometimes  slightly  in- 
clined, of  traprock  and  basalt,  to  which  some  coun- 
tries are  indebted  for  their  picturesque  aspect,  have 
been  at  some  distant  period  submerged,  and  exposed 
to  the  action  of  a  submarine  volcano,  which  has 
covered  them  with  its  products. 

In  such  cases,  when  the  volcano  is  in  repose, 
it  is  obvious  that  submarine  deposits  of  every  kind 
— including  animals  and  plants,  if  the  depth  be 
not  too  great — will  be  found  superimposed  upon 
the  lava.  Accordingly,  when  the  ocean-bed  is 
upheaved  to  the  light  of  day,  we  find  a  sheet  of 
basalt  between  two  beds  formed  of  the  debris  of 
marine  animals. 

In  Iceland  we  find  subaerial  volcanoes  side  by 
side  with  others  of  submarine  origin,  the  latter 
having  been  upheaved  to  the  light  of  day  long  after 
their  activity  had  ceased.     The  first  are  the  Jokuls, 


MAURITIUS.  327 

high  mountains  which  abound  in  the  ishind.  The 
north  and  south  of  Iceland  present  an  as|-»ect  tho- 
roughly characteristic  of  these  facts,  ^^'e  there  find 
immense  plateaux,  whose  submarine  origin  is  plainly 
indicate!  by  alternate  beds  of  basalt  and  basaltic 
conglomerate. 

The  Isle  of  France  (Mauritius)  has  all  the  cha- 
racters of  a  submarine  volcanic  ibrmation,  which  has 
been  elevated  en  masse  subsequently  to  the  cessation 
of  the  eruptions.  Bourbon,  the  near  neighbour  of 
Mauritius,  presents,  on  the  contrary,  the  appear- 
ance of  the  ordinary  volcano,  formed  by  the  repeated 
coolings  of  lava-streams  flowing  from  two  or  three 
sources  constantly  above  the  level  of  the  sea,  and  one 
of  which  is  in  incessant  activity. 

Allowing,  however,  that  the  remarks  of  Mr,  Poulett 
Seroi  e  are  well-ibunde  1,  it  must  be  owned  that  they 
are  subject  to  numerous  exceptions.  The  remark- 
able investigations  of  M.  S  .inte-Claire  Deville  have, 
in  fact,  demonstrated  tliat  the  nature  of  volcanic  pro- 
ducts V;  ries  ;i(<  ording  to  the  length  of  time  that  the 
volcano  has  been  in  activity.  It  would  lead  us  too 
far  from  our  special  subject  to  discuss  this  interesting 
question,  but  we  may  indicate  in  a  very  few  words 
one  of  the  many  results  obtained  by  M.  Deville.  A 
volcano  seems  to  have  its  period  of  youth  anl  its 
p(  rio  1  of  i)V\  age.     During  the  first  period,  lavas  are 


M28  THE  BOTTOM  OF  THE  SEA. 

ejected;  during  the  second,  basalts.  If  a  volcano  which 
vomits  lava  is  in  repose,  we  may  always  expect  a 
new  eruption.  When,  however,  the  lava  is  succeeded 
by  basalt,  we  may  be  equally  sure  the  volcano  is  on 
the  eve  of  extinction.  We  must,  therefore,  be  careful 
not  to  pronounce  too  absolutely  as  to  the  marine 
origin  of  volcanic  products  from  their  nature  and 
aspect. 

8.  Bottom  of  the  Sea  brought  to  light  in  consequence  of  the  Eruption 
of  "feubmarine  Volcanoes. 

If  a  mountain  belching  fire  is  lifted  above  the 
level  of  the  sea  by  the  actiou  of  some  subterranean 
fire,  it  carries  with  it  the  marine  formations  to  which 
it  had  served  as  a  support.  The  same  expansive  force 
acting  upon  a  larger  scale,  and  not  limiting  its  effects 
to  the  elevation  of  the  mountain,  will  raise  to  the  light 
of  day  a  more  extende  1  region  of  the  submarine  world, 
with  all  the  layers  of  debris,  sometimes  of  very  ancient 
formation,  which  cover  it. 

This  is  what  we  observe  to  have  happened  in 
Mauritius  and  two  neighbouring  islands.  The  con- 
figuration of  the  northern  part  of  Mauritius  is  that  of 
a  level  plane,  formed  of  a  recent  calcareous  rock,  com- 
posed of  polypi  analogous  to  the  coral.  It  covers  the 
volcanic  rocks  which  elsewhere  form  the  summits  of 
ihe  island.      The  superposition  of   madrepores  and 


CORAL  REEFS  OF  TEE  PACIFIC.  ^2r. 

corals  upon  volcanic  products,  is  an  evident  proof 
that  their  formation  was  subsequent  to  the  emission 
of  the  lava  upon  which  they  had  planted  themselves 
when  it  was  sufficiently  cool.  But  polyps  live  under 
water.  The  lava  therefore,  in  this  instance,  must 
have  been  of  submarine  origin ;  the  ocean-bed  thus 
formed  was  long  afterwards  upheaved  to  the  light  of 
day. 

By  far  the  greater  part  of  the  surface  of  a  group  of 
islands  situated  a  little  to  the  east  of  Java,  is  com- 
posed of  beds  of  coral,  in  all  respects  similar  to  those 
which  are  still  in  formation,  and  which  constitute 
the  well-known  dangerous  reefs  of  the  Pacific.  It 
is  obvious  that,  in  this  instance  also,  the  coral  })ol}  pi 
had  taken  up  their  abode  on  the  cooled  lava,  ai.d 
that  the  whole  mass  was  afterwards  elevated  above 
the  ocean,  as  in  the  case  of  Mauritius. 

In  the  island  of  Pulo  Nyas,  to  the  westward  (►f 
Sumatra,  beds  of  coral,  similar  to  those  of  the  neigh- 
bouring seas,  have  been  raised  to  a  height  of  many 
hundreds  of  yards. 

In  the  earthquake  which,  in  1820,  destroyed  a 
part  of  Acapulco  (as  described  in  a  previous  chapter), 
the  level  of  the  sea  remfiined  during  two  hours 
about  30  feet  below  its  ordinary  level,  in  conse- 
quence of  the  land  having  been  raised  to  that 
extent.     On  the  other  hand,  we  remark  a  permanent 


330  THE  BOTTOM  OF  THE  SEA. 

elevation  of  tlie  shore  at  Chili,  to  the  extent  of  two 
or  three  yards,  in  consequence  of  an  earthquake 
which  destroyed  Taliuano  in  the  Bay  of  Conception. 

It  would  be  possible  to  multiply,  very  greatly, 
examples  of  these  upheavals  of  the  submarine  soil. 
We  have  only  to  recall  the  frequent  formation  of  new 
islands,  alluded  to  in  a  previous  chapter. 

The  sudden  changes  which  actually  take  place  in 
the  basins  of  seas  are,  in  most  instances,  easy  to 
verify.  Often  they  are  the  cause  of  terrible  catas- 
trophes, which  affect  whole  populations,  and  leave  an 
indelible  impression  on  the  memories  of  tliose  who 
witnessed  or  suffered  by  them. 


881 


(JRADUAL  CHANGES  OF  THE  BOTTOM  OF  THE  SEA. 


1.  How  the  gradual  change  of  tlie  Sea-bottom  can  b-  demonstrated 
— Modificiitions  which  the  Map  of  Einope  would  suffer  by  n 
graduiil  sulsidence  of  Thirty  Fttt  in  a  century— Paris  sul  - 
merged — Europe  as  it  would  be  were  the  Level  of  tlie  Sea  laised 
500  feet — Toulouse  and  Vienna  as  Seaports. 

We  have  studied  the  more  sudden  shocks  to  whicli 
the  earth's  crust  may  be  subjected.  Incessant  move- 
ments of  a  more  gradual  kind,  which  to  be  demon- 
strated must  be  studied  during  several  generations, 
also  influence  it,  embracing  vast  regions,  and  in- 
fluencing equally  the  bottom  of  the  sea  and  the 
highest  mountains.  Under  the  influence  of  such 
slow,  almost  insensible,  changes  of  the  earth's  crust — 
countries,  at  one  time  flourishing,  have  disappeared, 
and  others  have  risen  in  their  stead. 

So  long  as  our  study  is  confined  to  the  sea,  or  to 
the  interior  of  continents,  we  may  look  in  vain  ibr 
evidence  of  such  changes  ;  but  if  we  visit  the  shores, 
we  may  find  abundant  proof  that  the  ocean  is  either 
gradually  retreating  from,  or  slowly  gaining  on,  the 
land.     If  the  sea  be  apparently  retreating,   it   is  a 


382  THE  BOTTOM  OF  THE  SEA. 

proof  that  the  land,  at  that  particular  spot,  is  rising. 
If  the  sea  be  gaining  on  the  land,  we  may  be  assured 
that  the  soil  is  sinking. 

On  any  coast  terminated  abruptly  by  a  high  cliff, 
we  may  perceive  above  high  water-mark  an  easily 
distinguishable  line.  The  waves  disintegrate  the 
rocks.  They  are  aided  in  their  work  by  animals, 
of  which  we  have  spoken  on  a  previous  page.  The 
pholades  and  other  stone-borers  are  impelled  by 
their  instincts  to  select  for  their  abode  the  line  of 
demarcation  between  the  two  elements,  where  the 
air  and  water  may  be  said  to  strive  in  perpetual  con- 
flict. These  boring  animals  cannot  remain  con- 
tinually submerged,  but  the  presence  of  water  is  in- 
dispensable to  their  existence.  The  clifis  against 
which  the  waves  dash  are  better  suited  to  their 
existence  than  any  other  situation.  Wherever  we 
find  that  these  animals  have  established  their  abode, 
there  must  have  been  at  one  time  the  seashore.  If 
the  sea  gains  on  the  land,  the  colonies  of  pholades 
advance  higher  with  the  waves ;  if  the  sea  retires 
before  a  rising  contin.ent,  the  pholades  follow  in  its 
retreat. 

Where  the  waves  die  away  on  a  beach  only 
slightly  inclined,  a  coast-line  is  formed  of  I'ounded 
pebbles  and  rubbish,  across  which  the  waves  only 
[)ass   during   great    storms.     This   line   defines   the 


BI8E  AND  FALL  OF  COASTS.  333 

boundaries  of  the  ocean.  If  the  land  be  rising,  this 
coast-line  will  appear  to  recede  from  the  water, 
while  a  fresh  one  will  be  continually  in  course  of 
formation  by  the  retiring  ocean. 

The  encroachment  or  retreat  of  the  sea,  easily 
proved  in  such  a  case,  is  much  less  obvious  on  a 
rocky  or  very  steep  coast.  Where  the  ground  is 
nearly  horizontal,  a  slight  rise  in  the  level  of  the  sea 
will  cause  the  inundation  of  a  great  extent  of  country. 
The  encroachment  of  the  sea  on  an  abrupt  coast  is, 
on  the  contrary,  insensible;  and  a  number  of  ob- 
servations, often  repeated  at  considerable  intervals, 
is  necessary  to  obtain  a  definite  idea  of  the  phe- 
nomena. 

If  to  this  difficulty  in  making  observations  we  add 
the  complication  (caused  by  the  ebb-and-flow  of  the 
tide,  we  may  easily  comprehend  why  so  many  years 
have  been  necessary  to  demonstrate  and  accurately 
to  measure  the  sinking  of  the  land  on  the  coast  of 
Sweden. 

When  the  earth  is  thrown  up  around  us  with  a 
great  noise,  when  crevices  are  produced  in  an  instant, 
and  the  solid  ground  trembles  and  quakes  beneath 
our  feet,  we  can  have  no  difficulty  in  remarking  the 
facts.  But  although,  after  an  earthquake  or  other 
perturbation  of  that  nature,  the  country  remains 
cither  raised  or  lowered  several  yards,  the  inhabi- 


334  'THE  BOTTOM  OF  THE  SEA. 

tants  of  the  interior  of  a  continent  would  not  be  in 
the  least  aware  of  it,  nor  would  they  be  more 
sensible  of  a  slow  and  continuous  rise  or  fall  in  the 
level.  The  seaside  inhabitants  would,  liowever, 
recognise  it  by  the  obvious  change  in  the  level  of 
the  sea — the  measure  of  its  apparent  rise  or  fall  being 
equal  to  the  actual  rise  or  fall  of  the  soil. 

If  Europe,  sinking  uniformly,  laid  itself  open  to 
tlie  invasion  of  the  sea,  what  would  not  be  the  modi- 
fication of  its  map  after  a  comparatively  short  time  ? 
Suppose  the  whole  continent  to  sink  at  the  rate  of 
some  ten  yards  in  a  century :  at  the  end  of  fifty 
centuries,  or  5000  years,  the  level  of  the  sea  would 
have  risen  some  500  yards — a  result  which  would 
cause  many  rich  plains  and  opulent  cities  to  be 
engulfed.  Paris,  with  her  lofty  monuments  and 
her  hills,  would  have  disappeared  long  since ;  a  forest 
of  marine  plants  would  have  covered  this  beautiful 
city,  and  marine  animals  would  have  disported  them- 
selves in  her  streets.  The  sands  and  other  deposits 
with  which  the  sea  covers  its  bed,  as  with  a  vast 
curtain,  would  soon  cover  up  the  present  scene  of 
such  advanced  civilisation.  Paris  would  disappear 
beneath  the  sea,  as  Nineveh  beneath  the  sands  of  the 
desert. 

But  the  change  in  the  level  of  the  sea  need 
not  be  so  great  for  the  map  of  Europe  to  become 


EUROPE  SUBMERGED.  337 

unrecognisable.  The  irtap  at  the  commencement  of 
this  chapter  represents  the  appearance  which  would 
be  presented  by  Europe,  supposing  the  level  of  the  sea 
were  to  rise  some  500  feet.  Its  land-connection  with 
the  Asiatic  continent  would  then  be  broken ;  it  would 
become  an  archipelago  traversed  by  large  arms  of 
the  sea.  The  valleys  of  the  Vistula  and  the  Dnieper 
would  become  vast  sheets  of  water.  An  immense 
gulf  would  flow  up  the  ancient  valley  of  the  Danube ; 
a  narrow  channel  would  separate  it  from  an  interior 
sea  corresponding  to  a  large  part  of  Hungary.  Den- 
mark, the  low-lying  plains  of  Germany  and  of  the 
Netherlands,  would  be  replaced  by  the  ocean. 
England  and  France  would  be  very  much  cut  up. 
In  the  latter  would  be  found  three  large  gulfs,  corre- 
sponding to  the  present  courses  of  the  Seine,  the  Loire, 
and  the  Garonne;  fisliing-boats  would  anchor  over 
Bordeaux  and  Orleans,  and  make  land  at  Toulouse. 
A  narrow  isthmus  would  unite  France  with  Spain 
in  the  neighbourhood  of  Castelnaudary,  and  the  rich 
wine-growing  countries  of  central  France  would 
become  transformed  into  submarine  prairies. 

The  plain  of  the  Po  and  the  valley  of  the  Ebro 
would  make  way  for  deep  gulfs ;  though,  in  general, 
the  northern  shores  of  the  Mediterranean  would 
suffer  but  little  change.  This  would  not  be  the  case 
with  the  low  plains  which  constitute  Egypt  and  Cyre- 


338  THE  BOTTOM  OF  THE  SEA, 

naica.  They  would  become  one  vast  sea,  bounded  by 
the  mountains  of  Algeria,  Morocco,  and  Abyssinia. 

The  climate  of  this  part  of  the  world  would  in  conse- 
quence be  much  changed.  Immense  sheets  of  water 
would  cover  the  saline  steppes  of  Eussia  ;  they  would 
extend  into  Turkestan,  as  far  as  the  Siberian  mountains 
and  the  table-land  of  Gobi ;  to  the  south  they  would 
invade  the  larger  part  of  the  African  desert.  The 
remains  of  Europe  would  have  a  very  humid  climate, 
for  whilst  at  present  the  western  winds  alone  bring 
us  wet,  all  the  winds  would  then  be  of  oceanic  origin. 

We  can  hardly  go  further  into  the  discussion  of  the 
modifications  which  would  result  from  such  an  altered 
state  of  things ;  our  only  business  is  to  point  to  the 
important  part  which  the  conquest  of  the  sea  plays  in 
the  general  economy  of  nature. 


2.  Ancient  limits  of  the  Black  Sea— Drying-up  of  the  Russian 
Steppes. 

Such  changes  do  not  entirely  belong  to  fiction. 
The  works  of  Tournefort,  Cliandler,  and  Tott,  those 
of  Count  Potocki,  of  Prince  Gallitzin,  and  of  Pallas, 
unite  with  thgse  of  the  ancients  to  prove  that  the 
northern  coasts  of  the  Black  Sea  have  changed  very 
much ;  and  that  between  this  sea,  the  Caspian,  and 
Lake  Aral,  traces  are  to  be  everywhere  found  of  the 


AN  ANCIENT  SEA.  330 

former  presence  of  the  sea.  Pallas  (vol.  x.)  tliiiiks 
that  the  salt  lakes  of  the  steppes  of  Russia  and  Tar- 
tary  are  ancient  gulfs,  the  mouths  of  which  have 
been  choked  up  with  sand,  and  which  have  subse- 
quently been  considerably  reduced  by  evaporation. 

Originally,  says  Pureau  de  la  Malle,  the  Mediter- 
ranean was  a  lake  of  small  extent,  fed  by  the  Nile,  the 
Rhone,  the  Po,  and  many  other  less  considerable  rivers. 
The  ocean,  making  an  irruption  into  it,  inundated 
a  part  of  the  low  sandy  coasts  of  Spain,  of  Barbary, 
and  the  plains  of  Provence  and  Languedoc,  and 
of  course  flooded  the  coasts  of  Egypt  and  Asia  Minor, 
where  it  has  penetrated  to  the  foot  of  the  mountains 
and  hills. 

After  that  period  the  Mediterranean,  losing  much 
more  by  evaporation  than  it  gained  from  its  rivers 
and  the  Straits  of  Gibraltar,  then  very  narrow,  gra- 
dually contracted.  But  it  was  enlarged  again,  when, 
owing  to  the  volcanic  eruption  of  the  Cyanei  Scopuli, 
the  channel  of  the  Bosphorus,  and  the  plains  in 
its  neighbourhood,  had  opened  a  passage  to  the 
Euxine,  the  Caspian,  and  the  Lake  of  Aral,  and 
they  were  united  in  one  sea,  at  least  as  large  as 
the  present  Mediterranean.  All  the  low  plains  of 
recent  formation  were  covered  with  water  afresh ; 
but  the  sea  again  retired  until  an  equilibrium  was 
established,   and    it    lost    by    evaporation    what  it 


340  THE  BOTTOM  OF  THE  SEA. 

gained  by  the  influx  of  water.  It  has  since  pre- 
served nearly  its  present  form,  the  only  material 
changes  being  on  the  low-lying  coasts  and  about  the 
mouths  of  the  great  rivers. 


3.  Movements  of  the  Earth  in  the  Northern  Hemisphere — Subsid- 
ence in  the  North  of  Europe  and  of  America — Elevation  of  the 
Polar  Regions — Sinking  of  the  Coast  of  Sweden. 

Certain  portions  of  the  earth's  surface  sink ;  others 
rise,  apparently  perhaps  without  obeying  any  general 
law,  but  not  really  so.  Everything  goes  to  prove  that  in 
our  hemisphere  the  continental  mass  is  being  elevated. 
A  concave  bend  may  be  traced  from  the  south  of  the 
Baltic  to  the  Atlantic,  passing  by  Denmark,  the 
North  Sea,  and  the  Low  Countries.  Prolonged 
through  the  Channel,  it  is  probably  continued  under 
the  ocean,  where,  however,  we  cannot  follow  it ;  but 
it  is  demonstrable  again  to  the  north-east  of  North 
America,  and  at  Greenland.  On  the  inner  side  of 
this  bend,  which  marks  a  zone  of  subsidence,  the  bed 
of  the  former  ocean  is  in  process  of  elevation. 

The  line  of  subsidence  cannot  be  followed  to  the 
east  beyond  the  Baltic,  for  reasons  we  have  already 
mentioned ;  but  it  certainly  should  not  stop  where 
we  can  no  longer  demonstrate  the  phenomena.  In 
the  neighbourhood  of  Sweden,  where  the  oscillating 


SEESAW  MOVEMENT.  341 

motion  of  the  soil  is  from  east  to  west,  the  appearance 
of  the  phenomenon  is  that  of  a  seesaw  movement; 
the  north  rises  and  the  south  subsides. 

New  islands  have  appeared  in  the  Gulfs  of  Bothnia 
and  Finland  :*  if  this  should  continue  for  two  thousand 
yeais,  the  Gulf  of  Tornea  will  become  a  lake,  like  those 
which  occupy  the  depressions  in  the  granite  all  over 
Finland ;  and  eighteen  hundred  years  later,  Stock- 
holm will  be  united  to  this  province  by  the  Isles  of 
Aland,  transformed  into  an  isthmus. 

Sir  Roderick  Murchison  first  noticed,  in  1845,  the 
existence  of  a  line,  around  which  the  surface  of 
Scandinavia  appeared  to  turn;  but  the  honour  of 
first  demonstrating  the  movements  of  the  land  in 
Sweden  belongs  to  the  Swedish  naturalist,  Celsius, 
who  lived  at  the  commencement  of  the  last  century. 
He  published  his  opinion  that  the  level  of  the  Baltic 
and  of  the  North  Sea  gradually  fell ;  and  the  result 
of  a  large  number  of  observations  was  to  settle  the 
amount  of  this  subsidence  at  about  one  yard  in  a 
century.  The  rocks  on  the  borders  of  the  Baltic 
and  the  ocean,  which  had  formerly  been  the  hidden 
cause  of  much  disaster  to  vessels,  showed  in  his  time 
above  the  level  of  the  water.  The  fact  that  terra 
firina  gained  continually  on  the  waters  of  the  Gulf  of 
Bothnia,  was  proved  by  the  existence  of  many  ancient 

♦  See  "  Les  Oscillations  de  I'dcorce  terrestre,"  by  M.  H^ert. 


342  THE  BOTTOM  OF  THE  SEA. 

ports  at  a  distance  from  the  coast,  by  the  abandon- 
ment of  fisheries  dried  up  or  converted  into  shallows, 
and  the  conversion  of  islands  into  continuous  land. 

The  facts  stated  by  Celsius  were  exact,  but  his  ex- 
planations were  erroneous.  In  1802,  Playfair  assigned 
their  true  cause  by  attributing  the  observed  changes 
to  the  movement  of  the  land. 

His  opinion  was  confirmed,  in  1807,  by  Leopold  de 
Buch,  who  discovered,  when  he  was  travelling  in  Scan- 
dinavia, the  gradual  elevation  of  the  whole  country 
between  Frederickshall  (Norway)  and  St.  Peters- 
burg. He  thought,  without  being  certain,  that 
Sweden  rose  more  than  Norway,  and  that  the  effects 
were  more  rapid  in  the  north  than  in  the  south. 

At  the  commencement  of  the  eighteenth  cen- 
tury, lines  had  been  cut  in  the  rocks  to  indicate 
the  ordinary  level  of  the  sea  in  calm  weather.  These 
data  were  examined,  in  1820  and  1821,  by  the  officers 
charged  with  the  pilotage,  and  new  lines  were  cut. 
During  this  interval  of  time  the  level  of  the  Baltic 
had  sunk,  but  not  everywhere  equally  during  equal 
times. 

Nilson  declared,  in  1837,  that  Scania,  the  most 
southern  province  of  Sweden,  seemed  to  have  sunk 
during  several  centuries.  This  Swedish  savan  at  the 
same  time  cited  a  number  of  facts  in  support  of  his 
novel  statement.     A  large  stone  near  Talbourg,  the 


SEESAW  MOVEMENT.  343 

distance  of  which  from  the  sea  had  been  measured 
by  Linnaeus,  in  1749,  was  more  than  30  yards  nearer 
the  shore  in  1837.  Certain  maritime  towns  were 
being  constantly  invaded  by  the  sea,  the  level  of  some 
of  the  streets  being  below  that  of  the  lowest  tides. 

An  entire  province,  heretofore  called  Witlanda,  and 
situated  between  Pillau,  Brandenburg,  and  Bolga, 
at  the  period  when  the  Teutonic  Order  flourished,  is 
now  completely  submerged.  Moreover,  the  soil  of 
Denmark,  of  Norway,  and  of  Sweden  contains  de- 
posits of  shell  entirely  similar  to  those  which  are 
formed  at  the  bottom  of  the  neighbouring  seas.  The 
soil  of  Scania  contains  none.  Therefore,  at  no  very 
remote  period,  Denmark,  and  certain  parts  of  Norway 
and  Sweden,  were  submerged ;  but  not  so  Scania. 
The  first-named  countries  are  now,  on  the  contrary, 
raised  above  the  waters,  and  man  establishes  himself 
in  them;  Scania  sinks,  and  Witlanda  has  already 
disappeared. 

Such  are  the  observations  which  have  enabled  the 
celebrated  geologist.  Sir  Roderick  Murchison,  to 
conclude,  in  a  general  manner,  that  the  actual 
motion  of  the  Swedish  soil,  and  of  the  bed  of  the 
Baltic,  resembles  that  of  a  seesaw,  the  fixed  line  or 
axis  of  which  would  pass  to  the  north  of  Scania. 
The  south  falls,  the  north  rises. 


iU  THE  BOTTOM  OF  THE  SEA. 


i.  Elevation  of  Spitzbergen — Sinking  of  the  Western  Coast,  and 
Elevation  of  the  Eastern  Coast  of  Greenland— Gradual  Submer- 
sion of  tlie  Forests  of  Labrador  and  of  Nova  Scotia — Roman 
Constructions  engulfed  in  the  Low  Countries — Origin  of  the 
Zuyder  Zee — Failure  of  the  Dutch  Sea-dams—  The  Valley  of 
the  Somme  and  the  Coasts  of  Normandy  follow  the  movement 
of  subsidence  of  the  Low  Countries. 

Spitzbergen  is  going  through  a  phase  of  elevation. 
Ancient  coasts  are  now  about  50  feet  above  the 
level  of  the  sea.  Siberia  follows  the  same  move- 
ment. Timbers  floated  anfl  thrown  on  to  the  coast 
by  the  waves,  are  now  in  the  interior,  at  a  dis- 
tance of  40  or  50  kilometres  from  the  shore.  An 
ancient  island,  still  separated  from  the  continent  in 
1760,  was  connected  with  the  mainland  in  1820. 

The  line  of  subsidence,  of  which  we  have  spoken 
above,  passes  to  the  south  of  the  British  Isles,  the 
northern  portion  of  which  (Scotland)  has  been 
elevated  some  25  feet  since  the  Koman  period. 
It  commences  to  the  north-west,  between  Greenland 
and  Iceland.  The  ruins  of  ancient  monuments 
may  still  be  seen  beneath  the  water.  A  Danish 
naturalist,  Dr.  Singel,  has  proved  that  during  the 
last  four  centuries,  the  sea  has  encroached  on  the 
land  over  a  length  of  more  than  900  kilometres 
from  north  to  south — a  circumstance  which  had  made 
it  necessary  to   remove,    repeatedly,   some  factories 


COASTS  OF  GREENLAND.  345 

which  had  been  established  on  the  shore,  and  sub- 
sequently invaded  by  the  water. 

The  submerged  forests  in  Fundy  Bay,  Nova 
Scotia,  the  subsidences  at  otlier  points  on  the  coasts 
of  Labrador  and  Upper  Canada,  show  that  Davis 
Straits  and  the  north-east  of  America  are  in  the 
same  line  of  motion  as  Greenland. 

Several  very  flourishing  Danish  missions  existed 
in  Greenland  in  the  ninth  century,  as  is  proved  by 
papal  bulls.  These  coasts,  now  unapproachable  on 
account  of  the  ice,  which  entirely  shuts  them  in, 
possessed  at  that  time  an  active  and  industrious 
population.  Two  towns,  one  cathedral,  eleven 
churches,  and  three  or  four  monasteries,  show  the 
prosperity  of  these  colonies  in  the  middle  ages. 
The  channel  which  separated  Greenland  from  Ice- 
land was  frozen  over  during  the  winter,  but  each 
year  the  passage  had  been  free  in  the  warm  season, 
and  a  Danish  fleet  carried  supplies  to  the  colonists, 
in  exchange  for  the  products  of  the  chase  and  the 
fisheries. 

In  1408  the  ice  did  not  break  up.  Subsequently, 
communication  being  interrupted,  and  the  colonists 
separated  from  the  mother-country,  they  were  either 
massacred  by  the  Esquimaux,  or  perished  of  cold 
and  hunger.  These  coasts  have  since  become  still 
colder,  and  glaciers  have  covered  the  ruins  of  th© 


346  THE  BOTTOM  OF  THE  SEA. 

Danish  settlements.  The  cause  of  this  cooling  is, 
very  probably,  a  general  elevation  of  the  whole 
eastern  coast,  whilst  the  western  coast  has  subsided. 
The  elevation  has  had  a  double  effect:  it  has 
t'iminished  the  temperature  while  increasing  the 
altitude  of  the  country  ;  it  has  compelled  the  warm 
waters  of  the  Gulf  Stream  to  flow  more  to  the  east — a 
result  which  has  contributed  enormously  to  diminish 
the  temperature  of  the  country.  We  shall  not  be 
astonished  at  this,  if  we  consider  the  enormous 
influeuce  exercised  on  climate  by  marine  currents. 

The  Netherlands,  as  M.  Elie  de  Beaumont  has 
shown,  are  subsiding  gradually.  Koman  construc- 
tions may  there  be  seen  surrounded  by  water, 
haviug  long  since  been  passed  by  the  coast-line. 
Peat-beds,  at  one  time  important,  have  been  buried 
beneath  the  sea  during  the  historic  period.  As  the 
oceanic  waters,  filtering  through  a  porous  soil,  con- 
tinued to  rise,  the  Lakes  of  Haarlem  were  gradually 
enlarged,  until  at  the  end  of  the  seventeenth  century 
they  united  to  form  an  inland  sea. 

It  is  all  in  vain  that  men  have  attempted  to  raise 
powerful  dams  against  the  encroachment  of  the  sea. 
The  dams  sink  slowly  with  the  soil  on  which  they 
rest,  and  there  is  no  doubt  that,  in  a  more  or  less 
distant  future,  the  barrier  wliich  they  oppose  will  be 
insufficient  to  protect  the  low-lying  plains  of  Holland. 


SINKING  OF  THE  CHANNEL.  347 

The  valley  of  the  Somme  and  the  coasts  of  Nor- 
mandy are  also  gradually  siuking.  Already  the  turf- 
pits  of  the  valley  of  the  Somme  are  below  the  level 
of  the  sea.  Submerged  forests,  whose  disappearance 
beneath  the  waters  is  proved  by  positive  docu- 
mentary evidence,  exist  off  the  coasts  of  Normandy. 
The  same  may  be  said  of  the  opposite  English  coasts. 
The  whole  of  the  Channel  is  sinking.  The  Straits 
of  Dover,  which  would  become  dry  land  by  a  slight 
elevation  of  the  soil,  are  therefore  but  little  likely 
to  serve  as  a  means  of  communication  between 
France  and  the  British  Isles.  There  are  two  reasons 
to  convince  us  that  it  must  enlarge :  first,  in  con- 
sequence of  the  action  of  the  sea  on  its  shores ;  and, 
secondly,  on  account  of  the  subsidence  of  the  sur- 
rounding countries. 


r».  Two  extensive  Zones  of  Subsidence  in  the  Southern  Hemispliere 
— They  are  separated  by  a  Zone  of  Elevation — The  Fiji  Islands 
have  been  sinking  during  300,000  years. 

Two  vast  regions  are  subsiding  in  the  southern 
hemisphere.  One  of  them  comprehends  the  nume- 
rous oceanic  archipelagos — the  Bass  Islands,  the 
Society  Isles,  the  Carolinas,  Gilbert's  Archipelago, 
Marshall's  Archipelago,  and  others.  Its  length  is 
more    than    8000    miles,    and    its    mean    breadth 


348  THE  BOTTOM  OF  THE  SEA. 

more  than  1200  miles.  Each  year  "has  furnished, 
and  still  furnishes,  proofs  of  the  disappearance  or 
diminished  size  of  islands  in  tliis  immense  zone. 

It  has  been  seen  in  a  preceding  chapter  how  the 
incessant  labours  of  the  coral  insects  compensate  for 
the  sinking  of  the  soil,  and  how  the  rapidity  of  the 
growth  of  the  coral  reefs  furnishes  a  measure  of  the 
rate  of  subsidence.  The  size  of  the  reefs  also  indi- 
cates the  epochs  since  which  the  movement  of  the 
soil  has  continued.  The  annual  growth  in  height  of 
the  polypiers  is  0"'*003.  Now  certain  reefs  are  several 
hundred  yards  in  depth.  Those  of  the  Fiji  Islands, 
for  example,  are  about  1000  yards,  those  of  the 
Gambier  Islands  about  400,  and  those  of  Tahiti  about 
80  yards.  If  the  growth  of  those  reefs  has  always 
been  at  the  same  rate,  300,000  years  have  been  neces- 
sary for  the  production  of  the  reefs  of  the  Fiji  Islands. 

The  coral  insects  grow  only  near  the  surface  of 
the  water :  they  have  therefore  sunk  1000  yards  at 
the  Fiji  Islands  since  they  first  commenced  their 
work,  and  that  has  been  during  a  period  of  300,000 
years. 

The  second  region  of  subsidence  comprehends  New 
Caledonia,  Australia,  and  the  basin  of  the'  Indian 
Ocean,  including  the  atolls*  of  the  Chagos  Bank  and 

*  An  atoll  is  a  circular  wall  or  reef  of  coral  enclosing  the  sea, 
within  which  it  resembles  a  small  lake. — Tb. 


SUBSIDENCE  IN  THE  SOUTHERN  HEMISFHEBE.     349 

the  Maldives.  The  polypiers  there  play  a  very  im- 
portant part. 

Between  these  two  zones  there  extends  a  vast  zone 
of  elevation.  It  is  formed  by  a  semicircle  of  vol- 
canic islands :  New  Zealand,  the  Kermandec  Islands, 
the  Friendly  Islands,  New  Hebrides,  the  Solomon 
Islands,  and  New  Guinea.  This  volcanic  line  bifur- 
cates. One  of  the  branches  passes  by  the  Philip- 
pines, Formosa,  and  Kamtschatka.  Its  direction  is 
therefore  first  east  and  afterwards  south-east.  It 
passes  th(5  Sandwich  Islands,  and  runs  parallel  with 
the  western  side  of  the  Andes  for  about  2500 
miles.  The  other  branch,  tending  westward,  passes 
Timor,  Java,  and  Sumatra.  The  rising  is  very 
evident  on  the  coral  banks  of  Mauritius,  the  Isles  of 
Reunion,  Madagascar,  the  Seychelles,  aud  the  Red 
Sea,  &c.,  which  serve  as  a  point  of  junction  between 
the  oceanic  and  continental  zones  of  elevatiou. 

We  have  already  explained  by  what  means  these 
variations  are  discovered ;  they  are  slow  but  con- 
tinual. We  are  still  far  from  being  acquainted  with 
the  laws  which  regulate  them,  but  it  is  a  great 
honour  for  our  century  to  have  clearly  demon- 
strated their  existence.  We  may  from  this  mo- 
ment say,  with  M.  Hebert :  "  In  spite  of  its 
apparent  immobility,  the  whole  surface  of  the 
earth  is  continually  undergoing  a  balancing  action 


S50  THE  BOTTOM  OF  THE  SEA. 

which  is  at  present  of  such  a  character  that  the  great 
continental  zones  are  rising,  whilst  the  great  oceanic 

basins  sink The  varied   surface  of  the 

earth  is  simply  due  to  a  series  of  movements,  which 
have  taken  an  incalculable  time  to  produce  existing 

results Let  us  carefully  remember  that 

our  measures,  adapted  to  our  own  comprehension  and 
to  the  length  of  our  existence,  are  borrov*^ed  from  the 
dimensions  and  motions  of  this  point  in  the  universe 
which  forms  our  habitation,  and  can  never  be  re- 
garded, whether  as  respects  space  or  time,  as  in  any 
sense  proportionate  to  the  dimensions  and  the 
duration  of  the  \\  orks  of  the  Creator  !" 


851 


ACriON  OF  RIVERS  AND  CURRENTS  ON  THE  BOTT'>»M 

OF  THE  SEA. 


1.  Choking  of  Ports  with  Sand — Deltas,  and  the  action  of  the  Tide 
upf)n  them — The  formation  of  Deltas  may  be  either  favoured 
or  retarded  by  Marine  Currents  according  to  circumstances — 
Deltas  formed  iu  Shallow  Seas— Rapid  growth  of  the  Delta  of 
the  Po  due  to  the  Clearing  of  the  south  side  of  the  Alps,  and  to 
the  Damming-in  of  the  Shores  of  the  River. 

The  movements  of  the  submarine  soil  are  among 
the  most  active  causes  of  variation  in  the  distribution 
of  h\nd  and  sea  on  our  globe ;  but  they  are  far  from 
being  the  only  causes  of  this  phenomenon.  The  rush 
of  the  waters  is  continually  causing  disintegration  of 
the  soil  where  the  current  is  rapid,  and  the  whole  of 
the  n^atter  thus  carried  in  suspension  is  deposited 
ivhen  the  waters  attain  a  position  of  rest  in  parts 
of  the  ocean  where  these  currents  cease  to  act.  This 
is  why  ports  choke  up,  unless  a  strong  current  of 
water  can  be  made  to  flow  through  them.  The  sand 
is  deposited  most  i-apidly  when  the  entrance  to  the 
port  follows  the  direction  of  a  current  parallel  with 


352  THE  BOTTOM  OF  THE  SEA. 

the  coast.  A  dam  constructed  at  a  given  distance, 
and  turning  the  current  towards  the  offing,  dimi- 
nishes the  accumulation  of  the  sand. 

In  consequence  of  the  same  action,  sandy  or  muddy- 
deposits  are  produced  at  the  mouths  of  rivers,  in  part 
embarrassing  tno  issue  of  the  waters,  and  sometimes 
becoming  sufficiently  important  to  constitute  islands 
extending  to  a  greater  or  less  distance  into  the  sea, 
and  called  "  deltas." 

We  have  already  seen  that  rivers  carry  a  large 
amount  of  rubbish  of  all  kinds  into  the  sea.  Kocks 
of  any  size  do  not  travel  far  beyond  the  mountains 
from  which  they  are  torn  ;  coarse  gravel  goes  a  little 
farther,  but  does  not  always  reach  the  sea.  In  the 
case  of  the  Ganges,  it  is  found  400  miles  from  the 
mouth;  whilst  in  that  of  the  Po,  it  is  not  dis- 
coverable beyond  Piacenza.  Bodies  carried  in  sus- 
pension go  farther  in  proportion  to  their  lightness. 

Mud  and  sand,  therefore,  form  essentially  the  base 
of  the  delta.  Fresh-water  or  land  shells,  the  remains 
of  salt-water  animals,  and  more  rarely  marine  shells, 
help  to  increase  these  deposits. 

Eemains  of  animals  of  large  size  are  also  found  in 
such  situations,  whether  they  have  been  carried  there 
by  the  river-current,  or  whether  the  delta  has  served 
them  for  a  habitation.  The  delta  of  the  Ganges  is 
inhabited  by  tigers  and  alligators;  all  the  human 


FORMATION  OF  DELTAS.  353 

bodies  thrown  into  the  river,  in  accordance  with 
Hindoo  custom,  are  stranded  there.  The  delta  of  the 
Mississippi  serves  as  a  retreat  for  numerous  alligators. 
The  deltas  of  the  Nile,  the  Rhone,  and  the  Khine 
are  covered  with  flourishing  cities,  while  venerable 
forests  occupy  the  immense  islands  which  obstruct  the 
mouths  of  the  larger  rivers  of  South  America.  The 
form  of  a  delta  is  triangular.  The  point  where  the 
river  first  divides  is  the  apex  of  the  delta.  The  base 
is  the  portion  of  coast-line  comprised  between  the 
mouths  of  the  two  inferior  branches.  Sometimes  two 
rivers  flow  into  the  sea  at  points  near  each  other, 
when  their  deltas  may  be  more  or  less  confounded ; 
in  such  cases  the  regularity  of  an  ordinary  delta 
must  not  be  expected.  The  two  deltas  combined 
form  a  network,  more  or  less  irregular,  of  islands  and 
canals.  The  Po  and  the  Adige,  the  Rhine  and  the 
Mouse,  the  Ganges  and  the  Brahmaputra,  are  ex- 
amples in  point. 

Many  causes  influence  the  collection  of  such  debris 
at  the  mouth  of  a  river.  They  have  been  examined 
with  minute  care  in  the  work  of  M.  Alexandre 
Vezian,*  to  whom  we  are  indebted  for  details. 

'J'he  more  extended  the  bed  of  a  river  is,  the  more 
materials  it  is  enabled  to  collect,  and  consequently 
the  more  rapid  is  the  formation  of  its  delta.     The 

♦  Prodrome  de  Geologic. 

2  A 


354  THE  BOTTOM  OF  THE  SEA. 

two   largest  deltas   are   those   of  the   Ganges  and 
Mississippi. 

The  tides  tend  to  hinder  the  formation  of  deltas. 
They  cause  the  waters  of  the  river  to  be  driven  back 
daily  with  considerable  agitation.  The  bed  of  the 
river  is  disturbed  and  broken  up,  and  the  great 
rapidity  of  the  current  of  the  falling  tide  augments 
such  disturbance.  The  Thames,  the  Tagus,  the 
St.  Lawrence,  and  the  Amazon  are  thus  influenced. 
1\\  however,  the  current  of  the  river  be  sufficiently 
strong  to  overcome  that  of  the  sea,  the  delta  is 
formed,  as  in  the  case  of  the  Ganges. 

An  inland  sea  offers  the  most  favourable  condi- 
tions for  the  establishment  of  a  delta.  The  Mis- 
sissippi, the  mouth  of  which  is  at  the  head  of  a  gulf, 
is  subject  to  conditions  intermediate  between  these 
two  extremes. 

A  current,  parallel  with  the  coast,  hinders  the  for- 
mation of  a  delta.  It  seizes  the  materials  as  they 
are  deposited  by  the  river,  and  sometimes  carries 
them  to  a  great  distance,  to  a  spot  more  calm.  This 
has  happened  in  the  instance  of  the  Amazon.  The 
current  of  this  immense  river  is  recognisable  a  hun- 
dred leagues  from  its  mouth.  The  sediment  which  it 
carries  in  suspension  is  considerable  ;  but  the  great 
equatorial  current,  which  flows  from  eas1>-south-east 
to    west-north-west    along    the    shores     of    South 


DELTA  OF  THE  GANGES.  355 

America,  carries  the  river-mud  along  with  it  as  far 
as  Guiana,  where,  far  from  it^  parent  river,  it 
forms  deposits  which  are  quite  analogous  to  those 
of  a  delta.  These  deposits  become  gradually  trans- 
formed into  dry  land,  and  they  may  be  considered  as 
the  delta  of  the  river,  carried,  bit  by  bit,  to  a  point 
westward  of  its  proper  destination. 

How  does  man  himself  proceed  to  work,  when  be 
wishes  to  recover  a  few  feet  of  land  from  the  sea  ? 
He  deposits  offshore  rocks,  stones,  and  whatever  else 
can  be  used  to  fill  up  the  deep.  1'he  river  at  its 
mouth  carries  with  it  light  sand  and  mud.  At  the 
time  of  its  rising,  immense  rafts  or  floating  islands 
of  forest  timbers  encumber  its  bed,  and,  becoming 
entangled  in  its  numerous  curves,  stop  and  form  true 
dams.  The  river  flows  round  them,  and  an  island 
is  formed.  Farther  on,  similar  islands  are  built  up 
near  the  sea,  where  the  deposits  are  continued  in  a 
shelving  form,  the  base  of  which  gains  daily ;  every 
hour,  every  minute,  brings  fresh  materials.  Nature's 
work  never  comes  to  a  standstill. 

It  is  evident  that  the  more  shallow  a  sea  is,  the 
more  rapidly  will  it  fill  up,  and  the  more  rapidly  will 
the  delta  be  formed.  The  great  depth  of  the  Bay  of 
Bengal  contributes  to  retain  the  formation  of  the 
delta  of  the  Ganges.  It  may  be  clearly  seen  on  a 
map  of  this  delta,  that  the  two  principal  exterior 


356  THE  BOTTOM  OF  THE  SEA. 

branches  fill  on  either  side  the  ocean  depths — build- 
ing up  two  immense  slopes,  separated  by  a  narrow 
ravine.  Ultimately  the  two  banks  will  become  con- 
nected, the  deep  water  between  them  being  gradually 
filled  up. 

The  rapid  formation  of  the  delta  of  the  Po,  and 
the  slight  depth  of  the  Adriatic,  into  which  sea  this 
river  pours  its  waters,  are  well-known  facts.  But 
other  causes  have  contributed  very  considerably  to 
this  effect ;  these  are  the  embankment  of  the  rivers 
and  the  clearing  of  the  forests. 

The  clearing  of  the  soil  and  the  destruction  of 
forests  tend  to  augment  the  quantity  of  water  which, 
in  the  rainy  seasons,  flows  down  into  the  river- 
courses.  Thus  man  himself  helps  to  increase  the 
quantity  of  material  that  streams  and  rivers  carry 
into  the  sea. 

Embankments  produce  similar  effects  by  aug- 
menting the  rapidity  of  the  current,  which,  in  times 
of  flood,  carries  sediment  much  farther  than  when 
allowed  to  spread  at  its  pleasure  over  vast  plains, 
where  it  deposits  great  quantities  of  mud. 

The  embankments  of  the  Nile,  of  the  Po,  and  of 
the  Mississippi,  show  how  the  growth  of  a  delta  may 
be  accelerated  by  narrowing  the  channel  of  the 
river. 

The  great  labour  of  embanking  the  Po,  and  effect- 


DELTA  OF  THE  NILE.  357 

ing  the  clearings  on  the  southern  side  of  the  Alps,  was 
performed  between  the  thirteenth  and  the  seventeenth 
centuries.  Since, then,  the  mouth  of  the  river  has 
advanced  with  great  rapidity  into  the  bosom  of  the 
Adriatic.  The  embankment  has  not  only  increased 
the  amount  of  materials  carried  by  the  Po  towards 
the  sea,  but  is  continually  raising  the  bed  of  the 
river,  which  is  actually  above  the  level  of  the  houses 
of  Ferrara. 

Similar  causes  have  produced  similar  effects  in  the 
case  of  the  Mississippi,  since  human  industiy  has 
taken  possession  of  the  vast  region  through  which 
this  river  and  its  tributaries  flow. 


2.  Egypt,  according  to  Herodotns,  a  present  from  the  Nile. 

The  Egyptians,  more  intelligent  than  ourselves, 
take  the  greatest  pains  to  store  up  the  waters  of  the 
Nile,  by  means  of  dams,  at  each  period  of  flood. 
They  receive  them  in  canals,  so  as  to  distribute  them 
more  completely  over  the  soil.  By  this  means  they 
also  diminish  the  force  of  the  current,  and  generally 
succeed  in  mitigating  the  otherwise  disastrous  effects 
of  the  inundation.  The  mud,  which  would  under 
other  circumstances  be  carried  to  the  sea,  is  depo- 
sited on  its  way,  and  fertilises  the  soil ;  the  materials 
which  would  form  the  delta  are   spread  over  the 


358  THE  BOTTOM  OF  THE  SEA. 

whole  extent  of  the  river's  basin.  The  delta  of  the 
Nile,  therefore,  increases  less  rapidly  than  those  of 
the  Mississippi  and  of  the  Po,  and  this  in  spite  of 
the  relative  smallness  of  the  basin  of  the  last-men- 
tioned river. 

The  ancient  Egyptians  knew  the  importance  of 
the  alluvial  matter  carried  in  suspension  by  rivers. 
Herodotus  (Book  II.  chap,  x.)  cites  the  opinion  of  the 
Egyptian  priests,  according  to  whom  Lower  Egypt 
is  a  present  from  the  Nile,  which  has  filled,  by  the 
deposition  of  its  mud,  an  arm  of  the  sea  enclosed 
between  Libya  and  the  Arabian  mountains.  He 
adds,  that  if  the  lead  be  thrown  at  the  distance 
of  a  day's  journey  from  the  sea  it  will  come  up 
well  covered  with  mud  from  a  depth  of  eleven 
fathoms.  Herodotus  bases  his  opinion  on  the  fact 
that  the  superficial  soil  of  this  country  is  a  blackish 
mud  from  Ethiopia,  which  contrasts  with  the  sand 
and  gravel,  the  ordinary  soil  of  these  countries. 

The  Egyptian  priests  also  remarked,  in  Hero- 
dotus' time,  that  under  M  ris,  900  years  before, 
if  the  Nile  in  its  annual  overflow  rose  eight  bits, 
it  watered  the  whole  of  the  plain  below  Memphis, 
and  that  it  then  produced  the  same  effect  only  when 
it  rose  fifteen  or  sixteen  cubits. 

Aristotle  speaks  of  the  variation  of  the  seas  in 
his  "  Treatise  on  Meteors."     *'  Egypt,"  he  says,  "  fur- 


DELTA  OF  THE  NILE.  359 

nishes  an  example  of  a  country  becoming  drier  and 
drier ;  it  is  entirely  formed  of  the  depositions  from 
the  Nile."  According  to  him,  the  Canopus,  or 
western  branch,  is  the  only  natural  one ;  the  others 
appear  to  have  been  dug  by  man  to  facilitate 
drainage. 

Plutarch  ("  Isis  and  Osiris  ")  says  that  in  ancient 
times  the  valley  of  the  Nile  was  covered  by  the 
sea,  as  is  proved  by  the  shells  met  with  in  the 
neiorhbourino:  desert,  and  the  saltness  of  the  wells 
dug  there.  Arabian  authors  of  the  middle  ages 
express  the  same  opinion. 

It  is  very  curious  to  remark,  that  ancient  ob- 
servers had  already  sufficiently  studied  this  ques- 
tion to  recognise  the  slow  but  continuous  elevation 
of  the  bed  of  the  river,  and  the  deposition  of  its 
suspended  matter  in  the  sea,  so  as  to  constitute  a 
delta.  From  this  elevation  of  the  bed  it  results, 
that  near  their  mouths,  in  very  flat  regions,  the 
rivers  often  flow  at  a  level  higher  than  that  of  the 
surrounding  plain,  so  that  at  each  flood  the  waters 
spread  over  the  surrounding  country,  and  cannot 
re-enter  their  bed  but  from  lakes. 

Often,  as  if  uncertain  of  their  course,  the  wateris 
divide  into  several  branches  to  reunite  farther  on. 
The  slightest  inequality  in  the  soil  forms  an  insur- 
mo  ntable  obstacle  to  their  progress.     The  waters 


360  THE  BOTTOM  OF  THE  SEA. 

seem  wearied,  as  of  a  long  journey — then  appear  to 
leave  with  regret  the  land  which  they  have  fertilised  ; 
they  follow  a  thousand  capricious  courses,  separating 
only  to  come  together  again ;  they  heap  up  sand 
and  mud,  as  if  to  reproduce  at  the  last  moment  the 
mountains  which  they  have  destroyed  in  their  force. 
But,  alas!  they  have  no  longer  that  power  which 
the  suddenness  of  their  descent  had  before  conferred 
on  them,  and  they  still  labour  to  diminish  it  after 
it  has  already  become  almost  insensible.  It  is  thus 
also  that  the  greatest  efforts  of  man  may  only  serve 
to  paralyse  his  powers,  when  he  works  without  the 
enlightenment  of  real  knowledge ! 


3.  Description  of  the  Delta  of  the  Mississippi — A  Village  at  Anchoi 
— Ships  lost  in  the  Sand  and  Mud  of  the  River. 

The  Mississippi  is  elevated  nearly  twelve  feet 
above  the  plain  about  a  mile  and  a  half  from  its 
banks.  The  main  stream  therefore  has  acquired  a 
tendency  to  send  its  ramifications  right  and  left, 
which  soon  become  the  subject  of  similar  phenomena. 

The  continual  deposition  of  soil  along  the  banks 
of  the  river  raises  its  bed  above  that  of  the  neigh 
bouring  plains,  and  it  therefore  runs  along  the 
summit  of  a  low  hill.  If  the  waters  overflow,  they 
spread  on  both  sides  of  the  hill,  and  are  never  able 


BANKS  OF  THE  MISSISSIPPI.  361 

to  return  to  the  channel  which  they  have  abandoned. 
They  travel  gradually  towards  the  sea  in  innu- 
merable tortuous  canals,  named  bayous,  which  occa- 
sionally swell  out  to  form  ponds  or  small  lakes. 
Like  the  principid  stream,  the  bayous  also  undergo  a 
process  of  gradual  elevation  of  their  beds.  A  second 
series  of  bayous  branch  out  from  the  first,  and  a 
third  from  these ;  the  elevation  of  these  bayous 
above  the  plain  becomes  less  as  the  distance  from 
the  main  stream  increases.  The  entire  region  pre- 
sents an  appearance  opposite  to  that  ordinarily  met 
with.  The  watercourses  occupy  the  crests  of  low 
hills,  and  their  importance  is  the  greater  as  the 
height  of  these  hills  increases.  Irrigation  becomes 
a  very  simple  matter  in  such  a  country. 

The  Mississippi  extends  very  far  into  the  sea.  It 
runs  out  between  two  banks  of  slight  elevation,  which 
it  continually  lengthens.  First,  it  converts  he  more 
or  less  deep  sea  into  shallows,  which  soon  become 
covered  with  a  forest  of  aquatic  plants  and  reeds. 
A  thick  layer  of  mud  is  deposited  at  every  flood, 
whi(jh  buries  the  stalks  of  the  plants,  and  elevates 
the  bottom  of  the  sea  in  such  a  manner  as  to  form  a 
species  of  submarine  delta.  This  deposit  is  increased 
from  year  to  year. 

Immense  rafts  of  forest  timber,  carried  to  the  sea 
and  again  <1  riven  back  by  the  waves,  become  covered 


362  TEE  BOTTOM  OF  THE  SEA, 

with  earth,  forming  floatiDg  islands;  and  being 
stranded  on  the  banks  described  above,  the  growth 
of  the  latter  is  much  facilitated. 

In  the  popular  "  Tour  du  Monde,"  published  under 
the  direction  of '  Mons.  E.  Charton,  an  interesting 
account  is  given,  by  Mons.  E.  Eeclus,  of  a  voyage  on 
the  Mississippi  as  far  as  New  Orleans.  He  describes 
all  the  phases  of  the  phenomena  of  deltas,  shows  the 
fresh-water  separated  from  the  ocean  by  a  moveable 
line  of  demarcation  of  sandy  mud,  forming  low  islands 
and  marshes,  and  ultimately  dry  land. 

"  All  night,"  he  says,  ''  our  vessel  dragged  over  a 
bottom  of  nauseous  mud ;  but,  far  from  complaining, 
I  congratulated  myself  on  the  opportunity  of  wit- 
nessing what  I  had  travelled  2000  leagues  to  see. 
What  can  be  more  interesting,  from  a  geological 
point  of  view,  than  this  vast  stretch  of  alluvial  soil 
in  a  semiliquid  state  !  Produced  by  the  slow  cor- 
rosion of  flowing  waters  during  many  ages  from  the 
mountain-chains  of  North  America,  this  sand  and 
clay  form  in  the  Gulf  of  Mexico  a  thick  bed  of  from 
200  to  300  yards  in  depth,  which  sooner  or  later,  by 
subsidence  and  the  influence  of  tropical  heat,  will 
become  transformed  into  vast  strata  of  rock,  and  will 
serve  as  a  base  for  fertile  and  populous  regions.  In 
their  work  of  creation  these  suspended  particles  are 
sifted  by  the  sea  into  deposits  of  various  sizes,  and 


MUD  OF  THE  MISSISSIPPI.  363 

are  thus  heaped  up  into  islands  or  new  shores ;  or 
perhaps,  carried  away  by  the  current  of  Florida,  are 
deposited  a  thousand  leagues  farther  off,  on  the 
Banks  of  Newfoundland. 

"  Towards  daybreak  the  captain  thought  of  a 
means  of  gettuig  off  the  mud-bank,  and  sent  one  ot 
our  boats  to  the  mouth  of  the  river  to  find  a  pilot. 
Some  miles  ahead  a  long  thin  black  line  seemed  to 
jut  out  into  the  sea,  like  an  immense  mole ;  beyond 
this  dark  line  the  river  was  distinguishable  like  a 
broad  silver  ribbon;  farther,  another  black  line, 
parallel  to  the  first,  was  visible;  and  still  beyond 
this  might  be  seen  the  blue  sea-waters  stretching  to 
the  horizon.  The  Mississippi  appeared  to  us  like  a 
canal  carried  right  out  into  the  sea  between  two 
long  jetties,  and  the  forty  or  fifty  sail,  just  apparent 
against  the  sky,  rendered  the  resemblance  still  more 
remarkable:  such  a  spectacle  will  one  day  be  pre- 
sented, on  a  smaller  scale,  by  the  Suez  Canal  pro- 
jecting into  the  waters  of  the  Mediterranean. 

**  When  we  approached  the  mouth  of  the  river  the 
tug  slackened  speed,  for  caution  was  necessary  in 
entering  the  buoyed  channels  which  lead  to  the 
entrance  of  the  river:  these  passes  are  very  dan- 
gerous because  the  currents,  both  of  river  and  tide, 
cause  the  depth  to  vary.  Ordinarily,  the  islands 
formed  by  the  subsidence  of  the  sus[)ended  matter 


364  THE  BOTTOM  OF  THE  SEA. 

grow  insensibly ;  but,  during  tempests,  the  sub- 
marine configuration  of  the  mouth  changes  com- 
pletely, and  it  is  unsafe  for  ships  to  attempt  an 
entrance  until  numerous  soundings  have  been  made. 
In  spite  of  his  native  audacity,  even  our  American 
pilot  felt  it  necessary  to  cast  the  lead  repeatedly. 

"  At  last  we  entered  the  course  of  the  river  itself,  and 
joyfully  felt  the  rush  of  the  current  against  the  sides 
of  the  vessel.  Nevertheless,  although  sailing  up  the 
Mississippi,  we  could  not  see  the  banks  of  this  won- 
derful river — it  appeared  to  us  like  a  river  flowing  in 
the  middle  of  the  sea.  The  only  indication  of  the 
submarine  banks  which  had  been  built  up  between 
the  salt  and  fresh  water,  was  an  occasional  muddi- 
ness  just  above  the  more  elevated  portions  of  the 
banks,  or  perhaps  here  and  there  the  bank  itself  was 
visible  in  dim  outline.  As  we  ascended  the  river, 
the  outlines  became  more  connected ;  what  had  pre- 
viously appeared  as  disconnected  or  accidental  ele- 
vations in  the  submarine  soil  now  acquired  the  ap- 
pearance of  a  continuous  line  of  demarcation,  and 
speedily  assumed  a  more  solid  and  definite  appear- 
ance, until  ultimately  it  rose,  a  solid  bank,  above 
the  level  of  the  surrounding  water.  At  this  point 
also  the  bar,  or  alluvial  dam  formed  across  the  river, 
attains  its  greatest  elevation. 

"  So  far  the  water  ploughed  by  our  keel,  and  left 


SAILING  UP  THE  MISSISSIPPI.  365 

bubbling  in  our  wake,  has  been  the  undercurrent  of 
blue  sea- water  which  flows  beneath  the  yellow  water 
of  the  river,  and  in  the  reverse  direction  ;  but  no 
sooner  have  we  touched  tlie  bar,  and  felt  the  ship's 
progress  impeded  by  the  resistance  of  the  mud,  than 
the  colour  of  the  water  in  our  wake  changes  to  a  dirty 
yellow,  and  the  already  muddy  current  is  rendered 
sensibly  thicker  by  the  disturbance  of  the  mud  at 
the  bottom.  The  helmsman  now  requires  a  firm 
hand  and  a  sharp  eye,  for  the  bar  is  nearly  a  mile 
long,  and  the  slightest  deviation  to  the  right  or  left 
may  entangle  the  vessel  irretrievably  in  the  mud. 
If  the  keel  once  stick,  its  peculiar  motion  raises  the 
mud,  the  light  particles  of  which  are  carried  in  a 
state  of  suspension  in  the  current,  whilst  the  heavier 
settles  around  the  hull ;  the  slow  motion  of  the 
ship  soon  allowing  it  to  collect  in  sufficient  quantity 
so  as  entirely  to  stop  the  vessel,  and  enclose  it  as  in 
a  wall  of  rock.  We  passed  a  lew  yards  from  a  magni- 
ficent three-masted  vessel  which  had  been  thus  be- 
leaguered, and  in  the  attempts  to  disengage  which 
fruitless  efforts  had  been  spent.  Enormous  banks 
of  sand  had  already  collected  around  it,  and  now  ap- 
peared like  great  masses  of  floating  cork. 

"The  village  of  Piiotsville,  the  wooden  huts  of 
which  were  visible  on  the  left  shore,  is  generally  know  n 
by  the  name  of  Balize.     This  name  really  belongs  to 


3GG  THE  BOTTOM  OF  THE  SEA, 

anotliei"  village  founded  by  French  colonists  on  the 
shore  of  the  south-east  channel ;  but  since  the  south- 
west channel  has  become  the  principal  enti'ance  to  the 
Mississippi,  the  pilots  have  at  one  and  the  same  time 
carried  their  industry  and  the  name  to  this  miserable 
town.  Certainly  few  places  on  the  earth  have  a 
more  wretched  appearance  ;  the  narrow  slip  of  earth 
on  which  the  houses  stand  is  at  once  the  shore  of  the 
river  and  of  the  sea.  The  waves  of  the  one  and  the 
floods  of  the  other  cover  it  in  turn,  and  mingle  to- 
gether in  a  labyrinth  of  slimy  and  offensive  ditches : 
wherever  a  little  solid  earth  permits  the  plants  to 
take  hold,  there  will  be  found  an  impenetrable 
jungle  of  wild  sugarcane  and  rushes.  The  wooden 
cabins  are  constructed  with  extreme  lightness,  so 
that  they  may  not  sink  in  the  soft  soil,  and  to  keep 
them  as  dry  as  possible  they  are  perched  on  the  top 
of  piles  like  stilts.  Moreover,  in  heavy  gales,  when 
the  waves  rush  over  the  bank  into  the  river  one 
after  another,  the  houses  of  Balize  might  easily  be 
swept  away  if  they  were  not  anchored  like  ships ; 
sometimes,  indeed,  the  village  does  drag  its  anchor. 
The  miasma  which  encircles  the  town  of  Balize  is 
the  everlasting  source  of  fever  and  death,  and  yet 
four  hundred  Americans  courageously  face  these 
dangers,  and  draw  what  profit  they  can  from  the 
succour  afforded  to  vessels  in  distress. 


SAILING  Ur  THE  MISSISSIPPI.  3G7 

*'  A  liglit  wind  blew  from  the  south,  and  our 
japtain  wished  to  profit  by  it  and  sail  up  the  river. 
Unhappily,  the  river  winds  in  the  most  distressing 
nuinner,  and  the  sailors  were  obliged  to  tack  about 
continually,  to  furl  and  unfurl  only  to  furl  again. 
They  could  scarcely  use  their  hands  for  fatigue  when 
the  ship  considerately  stuck  in  the  soft  mud  of  the 
bank.  Towards  evening  a  tug  came  and  pulled  us 
out  of  our  ridiculous  position.  Thanks  to  this  power- 
ful aid,  we  arrived  in  less  than  an  hour  at  the  point 
where  the  river  divides  into  several  distinct  channelsb 
In  the  last  hundred  miles  of  its  course  the  Missis- 
sippi seemed  to  me  like  a  gigantic  arm  stretching 
out  into  the  sea,  with  its  fingers  spread  out  on  the 
surface  of  the  water.  To  the  west  extends  the  Gulf 
of  Barataria ;  to  the  east  is  another  gulf,  known  as 
Lake  Borgue ;  to  the  south,  between  each  of  its 
channels,  a  little  marine  gulf  also  flows,  so  that  the 
whole  land-surface  consists  of  narrow  strips  of  coast- 
line, ceaselessly  demolished  by  the  waves,  ceaselessly 
renewed  by  deposition  from  the  river.  In  some 
j)laces  the  bank  is  so  little  elevated  above  the  sea- 
level  that  the  waves  almost  flow  over  into  the  Mis- 
sissippi ;  and  if  the  roots  of  the  rushes  did  not  bind 
the  soil  together  with  their  tenacious  hold,  the  beach 
would  soon  break  down,  and  a  new  channel  be  made 
for  the  '  Father  of  Yellow  Waters.' 


SG8  THE  BOTTOM  OF  THE  SEA. 

**  The  only  veg(  tation  on  these  narrow  huniid 
coasts  is  that  of  the  wild  sugarcane;  trees  cannot 
as  yet  find  any  hold  for  their  roots.  The  first  tree 
to  be  found  is  a  poor  stunted  willow,  which  has 
managed  to  drag  out  a  miserable  existence  on  the 
first  sufficiently  elevated  mound  of  earth  to  be  found — 
namely,  one  situated  about  twenty-four  miles  from 
the  mouth  of  the  river.  A  few  hundred  yards 
farther  up,  a  little  group  of  t\\o  or  three  more 
healthy-looking  willows  have  managed  to  plant 
themselves;  still  farther,  the  clusters  of  willows 
become  more  frequent :  at  last  they  grow  in  con- 
tinuous clumps,  and,  intermingling  their  foliage, 
form  a  curtain  of  pale- green,  which  hides  the  sea 
from  the  traveller,  and  gives  a  more  continental 
appearance  to  the  country."* 


4.  Rapid  growth  of  the  Deltas  of  the  Po  and  of  the  Mississippi — 
Delta  of  the  Nile  enlarged  by  Seven  Miles  during  the  Historic 
Period — The  Rhone. 

Dry  land  is  being  continuously  extended  seaward  at 

mouths  of  rivers  which  have  formed  deltas.     As 

the  older  channels  get  gradually  choked  up,  a  tinie 

comes  when  only  one  remains,  which  divides  again 

into  several  branches  nearer  the  sea.     At  the  same 

♦  Extracted  from  "  A  Voyage  to  New  Orleans,"  by  M.  Reclus. 


GROWTH  OF  DELTAS.  369 

time  new  deposits  are  built  up  against  the  assaults 
of  the  waves,  as  we  have  seen  to  be  the  case  with 
the  Mississippi.  It  results  that  the  delta  of  former 
times  is  no  longer  that  of  to-day,  and  that  the  navi- 
gable channels  are  always  in  couree  of  change. 

The  (channels  of  the  Nile  do  not  extend  more  than 
about  four  yards  in  a  year.  This  is  partly  owing 
to  the  system  of  canals  established  by  the  Egyptian 
priests,  partly  to  the  current  which  flows  along  the 
coast,  and  which  carries  a  large  part  of  the  suspended 
matter  towards  the  east,  and  occasionally  breaks 
down  its  banks. 

In  the  time  of  Augustus  the  sea  washed  against 
the  walls  of  Adria  (a  city  near  the  mouth  of  the  Po)  ; 
the  shore  is  now  eight  leagues  distant,  in  consequence 
of  the  growth  of  the  delta  of  the  Po.  The  increase 
from  the  twelfth  to  the  sixteenth  century  was  at  the 
rate  of  about  twenty-seven  yards  annually  ;  it  has 
augmented  since  then,  and  is  now  at  the  rate  of 
about  seventy-five  yards. 

The  d(.4ta  of  the  Rhone  advances,  perhaps,  fifty- 
five  yards  each  year,  and  that  of  the  Mississippi  about 
380  yards.  Tlie  itnmense  delta  of  the  Ganges,  situ- 
ated at  the  head  of  a  gulf,  must  grow  rapidly ; 
but,  as  the  spot  is  very  unhealthy,  it  has  never  been 
inhabited,  and  there  are  no  data  whicli  would  enable 
us  to  form  a  ju  Igment  on  the  subject. 

2  B 


870  THE  BOTTOM  OF  THE  SEA- 

The  outward  growth  of  the  heads  of  deltas  is 
proved  by  many  facts,  but  none  are  so  striking  as 
those  which  concern  the  delta  of  the  Nile.  At  one 
time  this  river  flowed  into  the  sea  through  seven 
branches,  of  which  there  were  three  principal  ones. 
Of  these  branches  two  only  now  remain — those  of 
Kosetta  and  Damietta.  The  exterior  branches  (the 
Canopus  and  the  Pelusiac)  are  filled  up,  and  the 
head  of  the  delta,  which  was  at  one  time  under 
the  parallel  of  Heliopolis,  is  now  about  seven  miles 
nearer  the  sea. 

In  all  deltas  the  relative  importance  of  the  various 
branches  of  the  river  is  constantly  changing.  In  the 
time  of  the  Etruscans  the  course  of  the  Po  was  the 
Po-di-Primaro,  but  now  the  principal  branch  is 
farther  north. 

The  head  of  the  delta  of  the  Ebone  is  at  Aries. 
The  western  branch,  now  called  the  Little  Khone, 
was  at  one  time  the  more  important.  It  was  itself 
successor  to  a  still  more  western  branch,  now  dried 
up.  The  principal  course,  at  the  present  time,  divides 
into  several  branches  before  falling  into  the  sea ; 
one  of  these  will,  in  course  of  time,  alone  remain, 
as  the  others  will  gradually  be  filled  up. 


ACCUMULATIONS  OF  SAND.  H71 


5.  Littoml  accurauLitions — Coast-lino  -Murine  Lagoons nnd  Pools  - 
Lagoons  movid  inland  by  the  ellt'cts  of  the  Dunes  in  Gascony — 
Villagos  burietl  Imnaith  the  Dunes  nfmr  St.  Pol-de-Le'on  in 
Brittany,  and  also  in  Guecouy — Bordeaux  menaced. 

The  elevation  of  a  shore  by  the  addition  of  fresh 
soil  is  effected  by  the  sea-waves  as  well  as  by  rivers. 
Every  coast  exhibits,  within  the  limits  occupied  by 
the  sea,  a  quantity  of  loose  sand  and  rounded  peb- 
bles. The  less  rapid  the  current  is  at  the  bottom  of 
the  sea,  the  slower  is  the  accumulation,  which,  how- 
ever, attains  great  importance  on  low  coasts,  giving 
rise  to  dunes,  bars,  and  a  number  of  other  phenomena, 
which  we  shall  indicate  in  a  few  words. 

We  have  seen  that  the  mass  of  loose  stones,  &c, 
thrown  up  by  the  sea  at  its  borders,  is  continuous 
along  eveiy  coast,  and  that  it  marks  what  is  called  the 
coast-line.  When  formed  of  fine  sand,  and  the  soil 
is  not  clayey,  the  action  of  the  wind,  in  conjunction 
with  the  waves,  causes  the  production  of  those  hills 
of  sand  called  dunes. 

Lagoons  often  accompany  the  coast-line  if  the  shore 
be  clayey,  and  if  the  country  be  sufficiently  flat  to 
allow  the  water  to  remain  in  any  slight  inequality 
of  the  soil,  or  to  flow  very  slowly  towards  the  sea. 

Bars  and  other  phenomena,  the  study  of  which 
would  carry  us  beyond  our  subject,  in  conjunction 


372  THE  BOTTOM  OF  THE  SEA. 

with  the  coast-line,  the  dunes,  and  the  lagoons,  con- 
stitute the  littoral  apparatus.  *'  They  combine  to 
form  a  very  decisive  line  of  demarcation  between  the 
region  of  storms  and  agitation  outside  the  sea,  and 
the  abode  of  peace  within  the  land."* 

The  coast-line,  in  some  cases,  may  become  a 
barrier  which  completely  separates  the  waters  of  a 
gulf  from  those  of  the  sea.  But  even  when  the  coast 
presents  no  hollow  for  the  collection  of  the  water, 
salt  lakes  or  lagoons  may  be  formed  if  a  line  of  rocks, 
visible  or  not  above  water,  should  exist  at  a  certain 
distance  from  the  shore,  and  form  a  bar  to  the  sand 
or  other  stuff  that  may  be  washed  up  by  the  sea. 
The  lagoon  may  retain  one  or  two  communications 
with  the  sea,  in  tlie  shape  of  channels,  or  it  may 
become  completely  enclosed. 

Marine  jponds  are  deep  lagoons ;  they  are  numerous 
on  the  coast  of  France.  That  of  Thau,  near  Cette,  is 
one  of  the  most  remarkable.  If  a  lagoon  entirely 
separated  from  the  sea  does  not  receive  any  stream 
of  water,  it  dries  gradually,  and  increases  in  saltness. 
When  it  receives  a  river,  its  saltness  diminishes.  In 
any  case,  the  creatures  which  it  feeds  are  modified 
according  to  the  changes  in  the  composition  of  the 
water.  Thus,  the  lagoons  of  Finland  are  inhabited 
by  freshwater  animals,  and  also  by  a  kind  of  shrimp 

*  Elie  de  Beaumont,  Ler^ons  de  Geohgie  Pratique. 


FORMATION  OF  DUNE,S.  373 

which  is  able  to  live  in  water  less  salt  than  that  of 
the  ocean. 

The  encroachments  of  the  sea  on  dry  land  are  not 
confined  to  inundations ;  it  sometimes  bores  beneath 
the  sand,  which  it  throws  up  from  its  bosom.  The 
dunes  (so  called  from  the  Celtic  word  dun,  which  sig- 
nifies an  elevated  spot),  or  sandhills,  are  formed  on  the 
seashore,  as  in  the  African  desert,  by  the  action  of 
the  wind  on  the  loose  sand.  They  present  a  gentle 
inclination  towards  the  sea,  whilst  on  the  land-side 
they  are  terminated  by  an  abrupt  declivity.  Their 
height  is  t;enerally  from  15  to  20  yards,  but  in  rare 
instances  they  attain  a  height  of  80  yards,  which  may 
be  considered  the  extreme  limit. 

For  the  rapid  formation  of  dunes  it  is  necessary 
that  the  sea  should  leave  a  large  space  bare,  which 
subsequently  it  will  cover  with  its  waters  and  the 
sand  it  carries  with  it.  These  conditions  are  best 
fulfilled  on  those  coasts  where  the  daily  ebb-and-flow 
of  the  tide  leaves  a  large  extent  of  sand  exposed  to  the 
drying  action  of  the  sun  and  wind.  Another  condition 
on  which  the  increase  of  the  dunes  depends,  is  that 
the  sea-winds  blow  more  frequently  than  those  from 
the  land — otherwise  the  work  of  one  day  will  be 
undone  by  that  of  another. 

The  formation  of  dunes  is  sufficiently  simple.  Tho 
wind  from   the  sea   blowing  over  the  sandy  waste, 


374 


THE  BOTTOM  OF  THE  SEA. 


causes  an  inclined  i)lane  to  be  forinea,  up  wliii-h  the 
particles  of  sand  are  afterwards  driven,  and  having 
attained  the  summit,  fall  down  the  declivity,  which 
they  continually  enlarge.    At  the  base  another  sund- 


Fig.  65. — A  Village  buried  under  Sand  Dunes. 


hill  commences  its  inclined  plane,  and  the  same 
action  of  the  wind  effects  a  similar  transference  of 
the  sand  to  a  third  hill.  The  materials  of  each  dune 
are  thus  driven  from  one  drift  to  another ;  so  that 
they  are  continually  being  destroyed,  and  as  con- 


GROWTH  OF  DUNES.  375 

tinually  re-formed,  at  a  greater  distance  from  the 
sea.  As  the  sand  is  carried  farther  inland  by  this 
process,  it  makes  way  for  new  supplies  from  tlie 
inexhaustible  stores  of  the  ocean. 

These  waves  of  sand,  invading  the  land  by  the 
impulse  of  the  wind,  have,  like  the  sea-waves,  an  un- 
equal motion,  according  to  the  configuration  of  the 
ground.  Everything  must  alike  yield  to  their  con- 
stantly advancing  forces  :  cultivated  land,  forests, 
houses,  villages,  and  towns  disappear  beneath  them  ; 
even  pools  of  water  retire  before  them,  as  in  Gascony, 
where,  under  the  influence  of  the  dunes,  numerous 
saltwater  pools  are  pushed  farther  inland,  and  their 
level  constantly  raised. 

As  the  Mediterranean  is  almost  tideless,  the  dunes 
are  formed  there  with  much  less  facility  than  on  the 
oceanic  coasts.  On  the  latter  examples  may  be  cited 
of  villages  being  buried  like  caravans  in  the  desert. 

At  a  spot  near  St.  Pol-de-Leon,  in  Brittany, 
where  a  village  stood  in  1666,  a  few  sand-hillocks, 
with  a  few  chimneys  and  steeples  to  indicate  the 
original  site  of  the  village,  alone  remained  fifty  years 
after :  the  dunes  had  advanced  at  the  rate  of  about 
580  yards  every  year.  The  dunes  of  Gascony,  how- 
ever, do  not  grow  with  this  frightful  rapidity,  their 
progress  not  exceeding  some  25  yards  annually.  If 
the  progress  should  remain  constant,  at  this  rate  they 


376  THE  BOTTOM  OF  THE  SEA. 

will  reach  Bordeaux  in  '2000  years.  Several  Gascon 
villages,  the  names  of  which  are  transmitted  by  docu- 
ments of  the  middle  ages,  have  completely  dis- 
appeared. 

The  coasts  of  the  Netherlands,  La  Vendee,  Pata- 
gonia, and  more  especially  of  the  Sahara,  are  among 
the  more  important  fields  of  this  phenomenon. 


6.  Floating  Icebergs— Polar  Winters. 

As  we  have  already  explained,  floating  icebergs 
deposit  a  vast  quantity  of  earthy  material  at  the 
bottom  of  the  sea.  They  are,  in  fact,  one  of  the 
most  powerful  agents  of  transport.  As  we  approach 
the  poles,  floating  masses  of  ice  are  met  with.  They 
become  larger  and  more  numerous  as  we  advance, 
and  at  a  high  altitude  a  continuous  field  of  ice 
stretches  before  the  view,  and,  no  doubt,  joins  a 
continent  which  is  also  frozen. 

Great  danger  is  incurred  in  an  attempt  to  pene- 
trate these  regions.  Ships  are  in  constant  danger  of 
being  crushed  between  the  immense  masses  of 
floating  ice,  some  of  which  rise  to  a  height  of  40 
yards  above  the  level  of  the  sea,  which  corresponds 
to  a  submerged  thickness  of  280  yards.  As  they 
advance  they  gradnaily  melt,  and  distribute  on  their 


THE  ARCTIC  REGIONS.  377 

route  the  materials  which  they  liave  transported 
from  the  arctic  continents,  or  from  the  beds  of  the 
polar  seas. 

If  the  sailor  succeed  in  passing  the  zone  \vhei*e 
these  immense  masses  of  ice  float,  he  may  expect 


Fig.  66. — Floating  Glaciei-s. 

every  instant  to  see  the  sea  freeze  up  around  his 
vessel  and  keep  him  prisoner  for  entire  months,  in  a 
region  where  he  may  perish  of  hunger,  should  he 
escape  the  thousaud-and-one  more  immediate  dangers 
which  threaten  him. 


378  THE  BOTTOM  OF  THE  SEA. 

The  celebrated  arctic  explorers,  Captain  John 
Davis,  Sir  Edward  Parry,  8ir  John  Ross,  Sir  John 
I'raiiklin,  Captain  (now  Sir  Robert)  M'Clure,  Dr. 
Kane,  Captain  (now  Sir  Leopold)  ^['Clintock,  and 
others,  in  their  search  for  the  nortli-west  passage, 
have  only  too  clearly  demonstrated  the  dangers  of 
any  attempt  to  penetrate  these  regions.  Nor  ought 
we  to  omit  the  name  of  the  intrepid  and  learned 
De  Blosseville.  Sent  on  an  exploring  expedition  to 
the  coasts  of  Greenland  in  the  Lilloise,  he  and  his 
companions  must  have  perished  miserably  in  those 
inhospitable  regions,  for  not  a  trace  has  since  been 
discovered  of  them. 

The  ice-bound  ship  is  in  an  unsafe  position,  but 
its  release  may  be  attended  with  even  more  danger 
than  its  captivity.  Sir  Leopold  M'Clintock,  who  suc- 
ceeded in  discovering  a  fe^  remains  of  Franklin's 
expedition,  says :  *'  On  the  18th  of  August  we  had 
arrived  in  the  mid-channel  of  Mflville's  Bay,  in 
Lancaster  Straits,  when,  being  unexpectedly  encircled 
by  an  immense  accumulation  of  drift-ice,  we  found 
ourselves  compelled  to  pass  the  winter  in  the  midst 
of  one  of  those  vast  fields  of  ice  of  which  I  had 
often  heard  during  my  career  as  a  sailor.  Li  the 
course  of  the  winter  the  force  of  the  water  often 
opened  long  crevices  or  channels  in  the  solid  vault  of 
ice  which  covered  it,  and  these  solutions  of  continuity 


BBEAKINO-UP  OF  THE  ICE.  :J79 

were  produce; I  with  such  violence,  that  often  masses 
of  ice  were  thrown  up,  as  by  tlie  effect  of  a  mine, 
several  feet  in  the  air,  and  formed  banks  on  eithei- 
side  of  the  crevice  from  whicli  they  had  been  pro- 
jects h  During  our  captivity  we  were  able  to  cap- 
ture in  these  channels  of  open  water  about  70  sea- 
cows,  which  furnished  us  with  food  for  our  dogs  and 
oil  for  our  lamps. 

"  We  did  not  regain  our  liberty  until  the  25th  of 
April,  in  latitude  60°  30',  and  under  circumstances 
which  will  long  be  remembered  by  those  who  shared 
in  the  expedition.  A  violent  tempest  arose  in  the 
south-east ;  the  ocean,  stirred  from  its  depths,  broke 
up  its  icy  crust,  and  hurled  into  chaotic  disorder  the 
broken  masses  of  the  icefield,  threatening  a  score  of 
times  the  little  Fox  with  total  destruction.  Our 
salvation  in  these  critical  circumstances  was  due  in 
the  first  place  to  Providence,  and  secondarily  to  the 
excellence  of  our  screw  and  the  form  of  our  stem." 

It  thus  appears  that  M*Clintock's  ship  had  drifted 
with  the  ice  from  the  75th  to  the  63rd  degree  of 
latitude — that  is  to  say,  a  distance  of  about  300 
leagues  from  its  starting-point.  A  violent  spring 
storm  broke  up  this  mass  of  ice,  which  then  drifted 
in  dangerous  confusion  towards  Newfoundland,  where 
it  would  meet  with  the  warm  waters  of  the  Gulf 
Stream,  and  gradually  disappear  in  the  ocean. 


380  THE  BOTWM  OF  THE  SEA. 


INFLUENCE  OF  LIFE  ON  VARIATIONS  IN  THE  BED 
OF  THE  OCEAN. 


1 .  Formation  of  Coral  Reefs  ;   limit  to  their  growth — Conditions 
favourable  to  their  development. 

Animal  and  vegetable  life  influences  to  a  great  extent 
the  various  changes  at  the  bottom  of  the  sea.  We 
have  already  seen  that  animals  of  the  smallest  size 
build  the  most  important  submarine  constructions, 
but  that  every  other  kind  of  existence  has  also  a  hand 
in  this  continual  transformation  or  modification  of  the 
submarine  world. 

The  tropical  seas  especially  swarm  with  an  immense 
variety  of  living  beings.  But  as  in  other  seas,  so  here 
in  warmer  waters,  the  shores  are  more  inhabited  than 
the  deeps,  and  at  a  little  distance  from  the  surface 
life  ceases  to  exist. 

We  will  attempt  to  describe  briefly  one  of  the  most 
interesting  and  wonderful  of  marine  phenomena,  that 
of  the  construction  of  coral  reefs,  ^^  hich  attain  such 
important  dimensions  in  the  Pacific  Ocean,  the  Indian 
Ocean,  and  the  West  Indian  seas. 


CONSTRUCTION  OF  CORAL  REEFS.  381 

Polypiers  continue  to  grow  until  they  have  reached 
the  surface  of  the  water.  The  construction  of  coral 
may  be  likened  to  a  forest ;  intervals  are  left  com- 
parable to  those  between  the  branches  of  a  tree  and 
the  trees  of  the  forest.  Animal  remains — partly  de- 
rived from  the  decay  of  some  parts  of  the  coral,  partly 
consisting  of  the  debris  of  molluscs  and  fish — fill  up 
the  gaps,  and,  in  the  manner  of  a  chemical  cement, 
serve  to  bind  the  whole  into  a  compact  mass. 

The  coral  insects  absorb,  particle  by  particle,  the 
carbonate  of  lime  from  the  water,  and  they  deposit 
it  afterwards.  The  carbonate  sometimes  appears  in 
a  mud<ly  form,  and,  hardening  by  exposure  to  air, 
appears  very  similar  to  chalk.  This  phenomenon  is 
very  remarkable  in  the  Bermudas,  where  it  has  been 
studied  by  the  naturalist  Nelson:  "After  having 
observed  the  decomposition  of  shells  and  polypiers 
from  the  less  calcareous  to  the  clumps  of  meandrinae 
and  astreae,  not  only  in  situ,  but  m  the  masses  which 
had  been  detached  by  means  of  the  diving-bell  for 
the  works  of  the  arsenal,  I  do  not  hesitate  to  affirm 
a  common  origin  for  the  chalk  of  the  Bermudas  and 
the  banks  of  stone,  more  or  less  solid,  which  constitute 
the  islands  themselves — only  that  the  latter  result  from 
the  accumulation  of  fragments  mechanically  broken, 
whereas  the  rock  or  chalky  paste  is  due  to  the  de- 
struction, owing  to  prolonged  submersion,  of  the  mem- 


382  THE  BOTTOM  OF  THE  SEA. 

branous  tissue  which  penetrates  the  whole  mass,  and 
which  is  then  separated  from  the  calcareous  matter 
contained  in  its  meshes.  The  former,  by  its  precipi- 
-tation,  forms  that  soft  whitish  substance,  analogous  to 
chalk,  which  is  found  in  the  bottoms  of  creeks  and 
gull's  mixed  with  shelly  sands,  the  debris  of  polypiers, 
well-preserved  shells,  and  consi'lerable  masses  of 
meandrinae  and  astreae." 

The  coral  insects  loye  warm  water  and  constant 
agitation.  This  last  circumstance  gives  a  very  cha- 
racteristic appearance  to  the  calcareous  deposits  which 
accompany  them.  Crystals  of  carbonate  of  lime  are 
deposited  in  the  liquid  mass,  and  become  centres 
around  which  new  molecules  of  the  same  matter  group 
themselves.  The  constant  agitation  of  the  water  gives 
a  rotatory  motion  to  the  little  solid  nuclei  already 
formed,  whilst  continued  deposition  goes  on  in  such 
a  manner  as  to  give  them  a  spherical  form.  The 
rock  thus  acquires  a  peculiar  texture,  called  oolitic. 

Lastly,  we  may  observe  that  coral  does  not  flourish 
except  in  limpid  water  and  on  a  rocky  bottom. 


LIVING  FORCE  lUBESISTIBLE,  383 


2.  Life  and  Inanimate  Nature — Coral  Insects  die  in  the  calra  of  Deep 
Waters — Explanation  of  the  formation  of  tlie  De.  p  Kocfs  of  the 
Pacific  Ocian — Coast  Reefs — Broken  lletfs — Bariier  Reefs  of 
Anstralia — How  the  Coral  Reef  becomes  an  Island. 

Darwin  observes,  in  bis  beautiful  work  on  the 
formation  of  Coral  Keefs,  that  when  the  ocean 
hurls  its  waves  against  the  shores  of  tlio  Pacific 
Islands,  they  find  in  it  an  invincible  enemy.  Never- 
theless, its  force  is  sometimes  withstood  by  obstacles 
apparently  very  feeble.  It  never  seems  to  repose. 
Its  mighty  billows,  raised  by  the  trade-winds,  roll  in- 
cessantly against  the  shores.  The  turbulence  of  the 
water  lashed  into  foaming  breakers  is  much  greater  on 
the  shores  of  these  islands  than  in  our  temperate 
remons:  and  no  one  could  observe  them  without 
feeling  convinced  that  rocks  even  of  granite  or 
quartz  must  eventually  yield  to  forces  so  consider- 
able, and  be  utterly  demolished.  These  little  isles 
of  coral,  however,  so  low,  so  insignificant,  resist  suc- 
cessfully the  assault  made  upon  them,  thanks  to  the 
intervention  of  another  force,  in  some  sort  opposed 
to  the  first,  which  takes  part  in  the  struggle.  The 
organic  forces  detach,  particle  by  particle,  from  the 
foaming  breakers  the  carbonate  of  lime,  which  they 
afterwards  reunite  in  a  symmetrical  form.  IMyriads 
of  architects  are  employed  in  this  work  night  and 


384  THE  BOTTOM  OF  THE  SEA. 

day,  and  we  see  their  soft  gelatinous  bodies,  aided  by 
the  law  of  vitality,  quell  the  brute  power  of  the 
waves,  against  which  neither  the  industry  of  man 
nor  the  inanimate  forces  of  nature  would  be  able  to 
struggle  with  success. 

Life,  apparently  weak  and  mean,  but  in  reality 
active  and  full  of  resources,  issues  victorious  from  an 
incessant  struggle,  in  which  inert  matter  threatens 
momentarily  the  destruction  of  the  frail  enemy  whose 
strength  she  continually  feeds.  Coral  insects  prefer 
a  current  of  water.  It  carries  away  from  them  the 
matters  rejected  or  secreted  by  their  bodies,  and  be- 
come innutritions,  or  even  as  dangerous  to  them  as 
poisons.  The  calm  reigning  in  deep  \\  ater  is  death 
to  these  minute  animals. 

The  coral  polypi  live  near  the  surface  :  according 
to  Darwin  and  Dana,  they  never  build  at  a  depth  ex- 
ceeding forty  yards,  whilst  other  species  live  at  much 
greater  depths,  even  reaching  to  400  yar<is.  How, 
then,  can  we  explain  the  great  depth  to  which  some 
of  the  larger  coral  banks,  like  those  of  the  Fiji  Islan^ls, 
descend  ?  Darwin  has  discovered  a  simple  explana- 
tion of  this  fact.  Founded  on  numerous  observa- 
tions, it  entirely  accords  with  wliat  geology  teaches 
us  respecting  the  crust  of  the  globe. 

Since  the  coral  insect  does  not  live  out  of  the  water, 
the  growth  of  the  reef  cannot  go  on  above  its  surface. 


FOIiMATION  OF  CORAL  ISLANDS.  385 

Here  the  sea  itself  assists  in  raising  the  elevation  of 
one  part  of  the  reef  by  disintegrating  or  breaking 
up  others.  When  the  reef  is  of  such  a  height,  says 
Chamisso,*  that  it  is  left  almost  dry  at  low-tide,  the 
coral  insects  abandon  their  work.  Above  this  line  a 
continuous  stony  stratum  may  be  observed,  com 
posed  of  the  shells  of  molhises,  of  echinoidae  with 
their  points  broken,  and  of  fragments  of  coral 
cemented  together  by  a  calcareous  sand  produced  b) 
the  pulverisation  of  the  shells.  The  heat  of  the  sun 
often  penetrates  this  mass  when  it  is  dry,  and  causes 
cracks  in  different  directions  ;  then  the  waves  have 
sufficient  power  to  break  off  masses  of  coral,  some- 
times six  feet  long,  and  four  or  five  feet  in  thickness, 
and  to  throw  them  up  on  the  reefs,  whereby  the  crust 
is  so  elevated  that  high-tide  only  covers  it  at  certain 
seasons  of  the  year.  The  calcareous  surface  does 
not,  however,  suffer  any  subsequent  disturbance,  but 
offtjrs  a  soil  to  the  seeds  of  trees  and  plants  brought 
by  the  waves,  upon  which  the  vegetables  grow  with 
sufficient  rapidity  to  form  very  soon  a  covering  for  its 
dazzling  white  surface.  Even  before  the  trees 
become  sufficiently  bushy  to  form  a  wood,  the  sea- 
birds  build  their  nests  on  the  once  bare  reef;  and 
land-birds,  lost  in  the  ocean  waste,  fly  to  it  as  a  place 
of  refuge ;  and  still  later,  long  after  the  coral 
*  Expedition  of  Kotzebue. 

2  0 


886  THE  BOTTOM  OF  THE  SEA. 

insects  have  finished  their  work,  man  appears,  and 
builds  his  hut  on  the  now  fertile  soil. 

The  coral  insects,  unable  to  live  in  fresh-water, 
are  interrupted  in  their  work  wherever  a  river  pours  its 
tribute  into  the  sea.  The  reefs  are  also  subject  to  very 
sudden  breaks  at  a  short  distance  from  the  sea,  if  the 
bottom  be  a  very  steep  incline ;  such  are  the  coast 
reefs,  or  broken  reefs,  so  called  on  account  of  their 
situation  and  of  tlieir  frequent  breaks. 

Sometimes  a  channel  of  considerable  width,  and  of 
more  or  less  depth,  separates  the  reef  from  the  coast. 
It  is  then  called  "a  barrier  reef."  Some  of  these  are 
of  very  great  extent.  One,  on  the  coast  of  New 
Caledonia,  is  100  leagues  long ;  another  follows  the 
eastern  coast  of  Australia  for  a  distance  of  400 
leagues,  almost  without  interruption.  The  channel 
which  separates  this  reef  from  the  mainland  is  from 
60  to  100  feet  in  depth,  and  its  width  yaries  between 
15  and  50  leagues. 

Coral  reefs  are  circular  when  the  coast  opposite  to 
which  they  are  built  is  that  of  a  small  island.  If, 
instead  of  an  island,  there  is  a  shallow,  such  as  would 
be  produced  by  the  summit  of  a  submarine  mountain, 
the  reef  becomes  converted  into  an  island,  in  the  form 
of  a  ring,  in  the  midst  of  which  is  a  lagoon,  generally 
communicating  with  the  ocean,  although  occasionally 
it  is  quite  enclosed.  Sometimes  the  lagoon  fills  up,  and 


*" ATOLLS"  OF  THE  PACIFIC.  387 

the  island  takes  the  form  of  a  circular  plateau.     In 
either  case  such  an  island  is  called  an  atoU. 

The  reciirrence  of  this  phenomenon  is  too  frequent, 
more  especially  in  the  Pacific  Ocean — its  cause  Las 
been  too  long  a  hard  nut  for  the  savans — for  us  to 
pass  it  by  without  saying  a  few  words  in  respect 
to  it. 

The  shape  of  these  islanls  led  to  the  belief,  that 
the  coral  insects  had  built  their  reefs  on  the  edges  of 
submarine  craters.  The  general  resemblance  be- 
tween them  and  certain  volcanic  islands  had  struck 
the  first  observers.  Such  islands  (as  Barj-en  Island 
and  othiers)  presented  a  circular  belt  of  mountains, 
interrupted  in  one  spot  by  a  canal  forming  a  com- 
munication between  the  sea  and  the  interior  lake. 
The  mountains  are  the  sides  of  a  crater,  the  bottom 
of  which  has  been  filled  up  with  the  invading  waters 
of  the  ocean.  The  same  general  character  is  at  first 
evident  in  the  appearance  of  an  atoll.  But  how- 
can  the  size  of  craters  which  correspond  to  atolls  be 
explained  ? — eleven  leagues  in  diameter,  such  as  that 
of  Bow  Island,  or  of  double  the  diameter,  as  in  several 
of  the  Maldive  Islands  ?  Again,  how  is  it  possible 
to  admit  that  the  Pacific  Ocean  is  studded  with  so 
many  volcanoes,  all  of  which  attain  about  the  same 
height  of  40  yards  ?  Lastly,  how  can  the  theory  of 
submarine  volcanoes  be  applied  to  the  formation  of 


388  THE  BOTTOM  OF  THE  SEA. 

barrier  reefs,  of  which  atolls  are  evidently  only  a 
particular  instance? 

We  have  already  explained  that  the  bottom  of 
the  sea  is  undergoing  a  constant  tliough  very  slow 
variation.  It  rises  in  some  points  to  sink  at  others ; 
and  this  movement,  which  requires  centuries  to  make 
itself  evident,  is  the  most  energetic  agent  of  the 
modifications  occurring  on  the  surface  of  our  planet. 
Darwin  has  very  ingeniously  applied  the  knowledge 
of  this  general  fact  to  the  explanation  of  atolls.  We 
give  his  theory  in  a  few  words,  as  follows : 

The  coral  insects  do  not  live  beyond  a  depth  of 
forty  yards.  They  aru  therefore  confined  to  the 
shallows,  or  to  the  neighbourhood  of  coasts.  On  the 
other  hand,  the  close  proximity  of  land  troubles  them 
for  various  reasons,  among  which  may  be  mentioned 
the  outflow  of  the  soft  waters  of  rivers,  and  the  agi- 
tation which  causes  mud,  &c.  to  be  held  in  sus- 
pension. They  therefore  remain  at  a  certain  distance 
from  the  shores.  Sooner  or  later  the  waves  break 
up  a  poition  of  the  coral  barriers,  and  wash  the  frag- 
ments over  the  reef  into  the  clear  channel  which  it 
thas  tends  to  fill.  When  the  reef  retiches  the  surface 
of  the  water  the  existence  of  its  artificers  becomes 
impossible.  But  if  the  soil  be  slowly  sinking,  there 
must  always  remain  sufficient  water  above  the  colony 
to  permit  of  its  continued  growth. 


FORMA  TION  0  F  "  A  TO  LLST  389 

Take  the  instance  of  an  island  slowly  sinking. 
The  coral  forms  at  first  a  continuous  reef  around  the 
coast ;  as  the  level  sinks,  the  coral  grows  upward. 
The  island  diminishes  at  the  same  time  in  size,  and 
leaves  a  channel  between  it  and  the  reefs,  which  then 
continue  their  growth.  A  time  would  at  length  come 
when  a  coral  reef,  in  the  form  of  a  ring,  would  be 
visible  surrounding  a  lagoon,  in  the  middle  of  which 
would  be  seen  the  remains  of  the  primitive  island. 
At  last,  when  the  island  shall  have  completely  dis- 
appearetl,  the  coral  ring — thanks  to  the  persistent 
eftbrts  of  tlie  coral  insect — will  remain  ;  it  will  sur- 
round a  lake  of  less  deptli  in  the  centre  than  at  the 
sides.  Later,  the  earth  continuing  to  sink,  the  depth 
of  the  middle  of  the  lake  will  continue  to  increase, 
whilst  the  edges  will  be  slowly  filled  up  with  the 
debris  arising  from  the  disintegration  of  a  portion  of 
the  coral  reef  The  lake  will  have  become  like  any 
other — :the  atoll  will  be  complete ;  it  will  itself  ])er- 
haps  finally  disappear,  or  increase  in  size,  if  the 
movement  of  the  earth's  crust  should  change  its 
direction. 

The   same  theory  evidently  explains  the  forma 
tion  of  coast  reefs  and  barrier  reefs,  since  these  are 
nothing  more  than  the  elements  of  the  atoll  built  in 
a  peculiar  situation  relative  to  the  land., 


890  THE  BOTTOM  OF  THE  SEA. 


8.  Slowne:5S  of  the  growth  of  Coral  Reefs — Florida  Keys— Destru<-tion 
of  Coijil  Islands  during  a  tempest  in  January  KS(J5 — Kegions 
in  which  Coral  Reefd  are  found. 

Although  it  is  certain  that  the  growth  of  coral 
reefs  is  very  slow,  yet  we  have  no  very  precise  obser- 
vations on  this  point.  Dana  estimates  tlie  growth  of 
the  madreporic  poly  pier  at  the  rate  of  (0°'*41)  more 
than  a  foot,  annually. 

According  to  an  observation  by  Hunt  in  West 
Key,  Florida,  in  1857,  a  meandriim  increased  six 
inches  in  radius  in  eleven  years.  According  to  the 
observations  of  the  same  naturalist,  an  occulina  grew 
rather  faster. 

Some  large  specimens  of  meandrinae,  observed  by 
Ehrenberg  in  the  Eed  Sea,  would  thus  appear  to  be 
thousands  of  years  old,  and  must  at  least  have  been 
contemporaneous  with  Moses.  But  Ehrenberg's  esti- 
mate of  size  was  perhaps  a  little  exaggerated. 

The  growth  of  a  reef  is  much  slower  than  that  of 
the  coral  which  composes  it.  The  sea  incessantly 
effects  its  partial  destruction.  Sometimes,  indeed, 
the  violence  of  the  waves  uproots  it  completely. 
Such  a  case  occurred  in  the  Palmerston  Islands  in 
January  1865,  as  described  by  Captain  Dunn,  of  the 
English  brig  Annie  Laurie,  in  an  account  to  the 


DESTRUCTION  OF  CORAL  ISLANDS.  8'Jl 

United  States'  consul  at  Tahiti.*  This  sailor  liad 
encountered  a  terrible  hurricane  in  south  latitude 
19°  20',  west  longitude  162°.  "I  found,"  says  he, 
"  the  islands  of  this  group  in  a  deplorable  state. 
The  Pcdmerston  group  originally  numbered  seven 
islands— six  only  now  remain  ;  the  north-easterly  one, 
and  a  part  of  the  coral  reef,  having  entirely  dis- 
appeared." 

Coral  reefe  and  islands  are  only  developed  in  tro- 
pical seas.  They  are,  however,  exceptionally  found 
in  the  Bermudas,  in  latitude  33°  N.,  a  circumstance 
due  to  the  warmth  of  the  waters  of  the  Gulf  Stream 
which  flows  by  these  islands.  They  are  not  met 
with  on  the  western  coasts  of  Africa  and  America,  in 
consequence  of  the  diminution  in  the  temperature  of 
these  parts,  occasioned  by  the  cold  marine  currents 
from  the  poles. 

In  no  part  are  the  coral  reefs  so  extensive  as  on 
the  coasts  of  New  Caledonia  and  Australia.  In  fact, 
these  seas  have  in  conseqnence  been  designated  the 
Coral  Seas. 

The  atolls  of  Tahiti  and  of  the  Biiss  Islands  arc. 
surrounded  by  sea  at  a  mean  temperature  of 
77°  Fahr.     Near  Peni  and  Chili  the  mean  tempera- 

•  Extract  from  a  letter  by  Mr.  Withing,  Commodore  in  the 
Aincric  in  Navy,  in.-erted-iu  the  Bulletin  Intematiotuil  dc  I  Obaer- 
vatoire  Imperial  de  I'ar.'s. 


392  THE  BOTTOM  OF  THE  SEA. 

ture  of  the  sea  is  60°  Fahr.  A  difference  of  tem- 
perature, amounting  to  17°  Fahr.,  therefore  arrests 
the  growth  of  the  coral  reefs. 

The  Persian  Gulf,  the  Red  Sea,  and  that  part  of 
the  Indian  Ocean  comprised  between  Africa  and 
Sumatra,  are  also  very  rich  in  coral.  We  must, 
however,  remark  that  these  seas  have  the  highest 
temperature  of  any  on  tlie  globe. 

For  the  same  reason  coral  flourishes  in  the  seas 
of  the  West  Indies,  and  on  the  eastern  coast  of 
Florida.  The  researches  of  Agassiz  show  that  the 
entire  peninsula  of  Florida  is  formed  of  rocks 
belonging  to  the  present  epoch,  and  that  these 
rocks  are  principally  composed  of  coral  reefs  and 
marine  shells.  The  southern  and  western  coasts  of 
Florida  are  surrounded  by  an  immense  number  of 
islands,  separated  one  from  another  by  very  narrow 
channels.  These  islands  are  in  many  instances 
connected  at  low-tide,  or  even  sometimes  only  sepa- 
rated irom  dry  land  by  flat  marshes. 

These  islands,  designated  ''  Keys,"  form  concentric 
lines  fronting  the  continental  shore,  from  which  they 
do  not  extend  a  great  distance,  the  most  remote 
being  ten  leagues  off.  They  rise  little  more  than 
from  six  to  twelve  feet  above  the  level  of  the  sea ; 
and,  like  the  land  itself,  are  composed  of  coral,  both 
in  masses  and  in  sand  thrown  up  by  the  soa,  the 


VEGETABLE  DEBRIii.  393 

whole  cement('d  together  by  tlie  infiltration  of  car- 
bonate of  lime. 

A  coral  reef,  still  inhabited  by  the  animals,  runs 
parallel  with  the  Keys,  following  the  same  curves, 
and  at  a  distance  varyinir  from  2000  to  6000  yards. 
Between  the  reef  and  the  Keys  there  is  a  navigable 
channel  (six  or  seven  fatiioms  in  depth),  which  com- 
municates with  the  open  sea  by  a  number  of  channels 
traversing  the  coral  reef. 

Generally  speaking,  the  banks  of  coral  forming 
the  reef  do  not  reach  to  the  surface  of  the  sea  ex.- 
cept  at  pnrticular  points,  where  the  accumulation  of 
broken  coral,  &c.  has  initiated  the  formation  of  little 
keys. 

The  Gulf  Stream  flows  beyond  the  reef  of  living 
coral. 


i.  Algaj — Submarine  Forests  and  Prairies — Flouting  Senwet  d  of 
the  Sargossa  Seas — Extension  of  the  Coasts  by  the  Ithizophora 
Mangle. 

Marine  vegetation,  like  marine  animals,  leaves  its 
debris  to  accumulate  at  the  bottom  of  the  sea ;  but, 
as  we  have  before  explained,  their  range  is  much 
more  limited  than  that  of  the  animals,  as  th<*y  are 
principally  confined  to  the  shallow  parts  of  the  sea 
and  to  the  neighbourhood   of  coasts.      Their   j)ro- 


394  TUJl  bottom  OF  THE  SEA. 

digious  growth  results  in  the  formation  of  submarino 
prairies,  which  serve  as  a  retreat  for  thousands  of 
animals. 

The  tangled  roots  of  the  algai  serve  to  bind  together 
and  strengthen  the  loose  bottom  of  the  sea,  and  in 
some  cases  near  the  coast  favour  the  extension  of 
the  land  into  the  sea — thus  tliemselves  assisting 
to  diminish  the  extent  of  the  domain  they  inhabit. 

In  the  middle  of  oceans,  more  particularly  in  the 
Atlantic,  enormous  quantities  of  seaweed  are  met 
with,  which  have  no  hold  on  the  bottom  of  the  sea, 
in  these  parts  of  great  depth.  The  quantities  of 
these  plants  are  so  enormous,  that  the  first  sailors 
who  met  with  them  mistook  the  appearance  they 
presented  for  dry  land,  and  were  terrified  to  find 
their  vessels  becoming  more  and  more  entangled  in 
the  weeds  which  thus  hindered  their  progress.  It  is 
now  known  that  these  immense  accumulations  of 
seaweed  are  due  to  a  species  of  circular  current  in 
the  vast  basin  of  the  sea,  towards  the  centre  of  which 
all  the  loose  floating  debris  detached  from  the  coasts 
tends  to  converge. 

A  tree,  the  Bhizophora  mangle  (mangrove),  has  a 
remarkable  influence  on  the  extension  of  the  coasts 
of  Guiana,  uniting  its  action  with  that  of  the  equa- 
torial current,  which,  as  we  have  already  seen, 
transports  the  delta  of  the  Amazon,  fragment   by 


COAST  VEGETATION.  395 

fragment.     This  exempHHes  the  variety  of  Nature's 
means  for  producing  the  same  result. 

The  mangrove  grows  abundantly  on  low  coasts 
and  in  lagoons.  Its  penlant  branches  ultimately 
form  its  roots.  At  first  they  swing  in  the  air,  of 
which  they  retain  the  moisture  like  the  finest  sponge. 
When  they  reach  tlie  soil  they  continue  to  grow  and 
increase  in  size,  penetrating  the  mud  like  ordinary 
i-cots.  They  resemble  so  many  columns  intended 
to  support  the  gigantic  branches  of  the  mangrove. 
Each  branch  thus  curiously  rooted  becomes  a  new 
trunk,  which  will  ultimately  transmit  sap  and 
strength  like  the  parent  stem.  The  roots  going 
out  from  the  new  trunk  give  more  solidity  to  the 
marshy  ground,  and  enable  the  natives  to  penetrate 
the  forests  formed  of  this  tree.  The  mangroves 
take  possession  of  all  the  shallows  as  they  are 
formed.  The  mud,  and  all  kinds  of  floating  bodies, 
are  arrested  by  their  roots  as  by  a  fine  net.  The 
algoe  consolidate  the  newly-formed  land  at  the  sea- 
side, and  the  accumulation  of  sediment  elevates  it 
on  the  land-side.  The  soil  in  this  part  soon  becomes 
too  dry  to  continue  to  support  the  mangroves.  The 
cocoanut  and  other  trees  replace  them,  and  by  their 
presence  complete  the  conquest  (;f  the  cciutinent 
over  the  ocean. 


396  THE  BOTTOM  OF  THE  SEA. 


INSIGNIFICANCE  OF  MAN  COMPARED  WITH  THE 
OCEAX. 

The  reader  has  now  been  introduced  to  a  little 
museum  of  submarine  wonders,  by  a  guide  who  has 
sometimes  perhaps  trespassed  on  his  patience,  but 
who  has  aimeH,  at  least,  to  be  instructive  without 
being  dull.  A  general  idea  of  the  form  of  the  ocean- 
bed,  and  of  some  of  the  mysteries  concealed  in  the 
abyss  of  waters,  has,  we  may  hope,  been  clearly 
given.  Aided  by  the  apparatus  of  the  diver,  we 
have  been  able  to  enjoy  a  few  moments  of  submarine 
life,  and  to  advance  some  steps  in  the  more  frequented 
valleys  of  the  ocean  landscape.  Is  the  author  to 
blame  if  he  cannot  find  the  means  for  extending 
these  excursions  still  further — if  he  cannot  defy  the 
very  laws  of  nature — set  at  naught  the  pressure  of 
800  atmospheres,  under  which  are  hardening  the 
marvellous  stratifications  upon  which  our  descendants 
will  live  and  flourish — see  without  light,  and  surpass 
in  agility  and  force  the  monsters  who  would  make 
us  their  prey?  While  we  are  anxious  that  these 
]acuna3  in  jouv  knowledge  of  the  sea  should  be  filled 


TELEGRAPHIC  CABLES.  397 

up,  it  is  only  prudent  not  to  be  too  venturesome  in 
an  element  for  which  we  are  not  adapted. 

Standing  on  the  shore,  we  look  with  wonder  on 
that  cable  fixed  to  the  rocks,  and  slowly  unrolling 
from  a  chain  carried  by  a  ship  steaming  seaward. 
It  would  almost  look  as  if  the  hardy  seaman  had 
shrunk  from  trustiiu^  himself  to  a  desert  without  a 
landmark,  and  had  contrived  this  means  of  preserv- 
ing iiis  communication  with  the  shore.  But  we 
know  well  enough  that  he  has  no  need  of  that 
thread  to  guide  him  safely  over  the  vast  labyrinth 
of  watei-s.  That  cable  means  something  quite  dif- 
ferent. If  we  choose  to  examine  the  shore-end, 
we  shall  find  that  a  few  copper  wires  care- 
fully enveloped  in  gutta-perclia  occupy  the  centre. 
Around  this  nucleus  is  a  firmly-twisted  cord  of  iron. 
The  heart  of  the  cable  is  thus  protected  so  that 
nothing  may  interrupt  the  track  destined  for  the 
transmission  of  thought.  When  resting  on  the 
bottom  of  the  ocean,  this  simple  apparatus  shall 
serve  as  the  medium  of  communication  between  one 
human  being  and  another  who  wish  to  converse 
together  though  thousands  of  miles  apart. 

While  a  just  pride  may  be  felt  in  the  audacity 
and  good  fortune  which  has  enabled  man  to  make  a 
pathway  for  thought  over  the  bottom  of  the  abyss, 
there  is  yet  much  in  this  very  achievement  to  make 


898  THE  BOTTOM  OF  THE  SEA. 

US  sensible  of  our  littleness.  After  all,  though  we 
can  make  signals  through  the  cable,  and  see  how 
they  work  at  the  two  extremities,  what  do  we  know 
of  the  whole  chain  of  communication,  or  of  the 
power  which  we  have  so  audaciously  forced  into  our 
service  ?  We  are  ignorant  of  a  thousand  mysteries 
in  the  route,  and  the  work  of  the  ocean  goes  on 
with  small  respect  for  the  noble  destination  of  the 
electric  submarine  conductor  of  thought.  Sponges, 
algse,  polypiers,  auatiferae,  and  serpularise  freely  make 
use  of  it  as  their  abode — feeling  no  disquiet,  whatever 
secrets  of  human  grief,  or  joy,  or  ambition  traverse 
their  support.  A  rupture  occurs,  however,  and  they 
who  laid  the  cable  fish  it  up  again,  at  tlie  same  time 
lifting  out  of  their  element  the  imprudent  adven- 
turers who  had  fastened  upon  the  rope.  He  studies 
them,  and  consoles  himself  for  his  ignorance,  as  the 
hare  laughed  at  the  fright  which  the  frog  caused  him. 
The  multitude  of  animals  which  cover  the  cable 
serve  not  only  to  hide  it  from  view,  but  to  increase 
its  volume  three  or  fourfold.  That  represented  in 
the  engraving  has  certainly  not  been  very  long 
under  the  water.  The  animals  and  plants,  at  first 
taken  by  surprise,  have  to  get  accustomed  to  its 
presence  before  they  weave  around  it  its  oceanic 
vestment. 

When   the  cable   is   laid   at  the  depth  of  some 


FOSSILISED  CABLES.  399 

thousands  of  yards,  the  operation  for  its  recovery  is 
extremely  delicate  and  laborious.  Any  agitation  of 
the  ship  might  injure  it;  its  weight,  added  to  that 
of  the  animals  and  plants  which  have  made  it  their 
home,  would  often  be  sufficient  to  make  it  break,  and 
in  such  a  case  the  broken  end  falls  back  into  the  ocean. 


ig.  »')7. — Telegraj)hic  Cable  at  the  Bottom  of  the  Ocean. 


Once  more  settled  at  the  bottom,  it  serves,  as  before, 
for  the  support  of  the  living  beings  who  clothed  it 
with  their  strange  forms  after  having  for  an  instant, 
by  its  fall,  disturbed  the  calm  repose  of  the  sub- 
marine solitudes.     At  some  remote  period,  when  the 


400  TEE  BOTTOM  OF  THE  SEA. 

work  of  ages  shall  have  raised  the  bottom  of  the  sea 
above  the  waters,  and  the  mountains,  which  now 
form  the  grandest  features  of  the  earth's  surface, 
shall  have  sunk  beneath  the  waves,  the  successors  of 
the  present  race  of  mankind  will  look  with  astonish- 
ment on  this  new  species  of  fossil,  the  relic  of  a  for- 
gotten civilisation,  buried  out  of  sight  in  the  same 
way  as  the  vestiges  of  the  past  which  we  ourselves 
are  so  interested  in  studying. 

Shipwrecks,  too,  with  the  debris  of  their  various 
freights,  will  lend  their  irrefragable  testimony  to  the 
former  existence  of  man,  and  increase  the  perplexity 
of  the  geologists  of  the  future.  Still  more,  in  the 
midst  of  the  most  sharply-defined  marine  deposits, 
the  observer  will  discover  the  remains  of  our  vanishing 
race.  He  will  see  artificial  tunnels  pierced  through 
the  most  varied  strata ;  and  in  these,  at  least,  he  will 
find  evidence  of  our  present  labours  to  reward  his 
researches.  If  hereafter,  not  contented  with  piercing 
the  mountains  to  avoid  the  labour  of  ascent  and 
descent,  we  drive  our  roads  beneath  the  seas  them- 
selves, what  would  come  to  pass  ?  Above  our  secure 
highway,  storms  and  cyclones  would  pass  harmlessly ; 
we  should  hear,  perhaps,  their  fearful  music,  and  be 
deafened  by  the  roar  of  the  waves,  or  the  rush  of  the 
locomotive  with  its  ugly  train  of  carriages ;  but  we 
should  speed  with  the  swiftness  of  the  wind  from  one 


TUNNELLING  UNDER  THE  SEA.  401 

ocean  shore  to  another,  and  defy  the  caprices  of  the 
winds  and  waves. 

But  the  geologists  and  engineers  of  former  ages 
need  not  despair.  We  are  yet  very  far  from  the 
accomplishment  of  these  marvels.  For  a  long  time 
to  come  the  monsters  of  the  deep  will  make  sport  of 
our  telegraphic  cables  ere  they  fly  before  the  breath 
of  the  locomotive,  and  the  discordant  noises  of  the 
submarine  tunnel. 

In  the  meantime,  as  a  foreshadowing  of  what  may 
be  anticipated  for  the  distant  future,  the  Thames 
has  been  securely  tunneled,  and  there  is  much  talk 
of  plans  for  cheating  the  storms  of  the  English 
Channel  by  driving  a  road  beneath  it  from  Dover 
to  Calais.  It  may  be  thought  there  is  too  much 
bravado  in  the  project,  but  the  Channel  is  little  more 
than  a  stream  compared  with  some  of  the  American 
rivers,  and  the  deptli  of  the  water  in  several  points 
is  not  more  than  from  20  to  25  feet.  Even  were 
this  design  accomplished,  we  should  be  far  indeed 
from  attacking  the  ocean  itself. 

Until,  as  the  skill  of  our  engineers  progresses,  we 
lose  all  dread  of  anything  crushing  in  our  tunnels, 
the  sea  will  demand  innumerable  victims,  and 
swallow  up  many  a  rich  argosy.  It  would  be  in- 
teresting to  make  an  approximative  estimate  of  our 
gains  and  losses  by  the  ocean,  so  as  to  ascertain  on 

2  D 


402  THE  BOTTOM  OF  THE  SEA. 

wliich  side  the  balance  of  the  account  lies.  But  a 
mere  enumeration  of  the  oceanic  imposts  would  be 
tedious,  while  a  history  of  our  gains,  of  the  various 
means  by  which  man  compels  tlie  ocean  to  pay  him 
tribute  in  return,  would  be  too  large  a  subject  for 
the  scope  of  this  little  book. 

Let  us  rather  turn  from  a  subject  so  full  of  painful 
memories  to  contemplate  man  in  contrast  with  the 
grandeur  of  creation.  The  thin  pellicle  of  the 
earth's  crust,  which  we  laboriously  scratch  here  and 
there  in  the  accomplishment  of  our  great  designs, 
hardly  counts  for  anything  in  the  harmony  of  the 
universe,  even  as  a  whole ;  its  modifications  by  our 
labours  are  of  small  account  indeed,  whether  re- 
garded for  their  grandeur  or  their  durability.  If 
the  intelligence  of  man  has  placed  him  at  the  head 
of  the  creation,  the  feeble  influence  that  he  can 
exercise  over  Nature  ought  to  humble  his  pride. 
All  that  he  can  accomplish  by  physical  labour  is 
almost  imperceptible  by  the  side  of  the  work  effected 
by  the  microscopic  infusoriae;  man,  the  giant,  is 
dwarfed  in  results  by  the  almost  invisible  atom ! 


UnXDOS :   FBINTED  BY  WILLIAM  CLOWES  AND  SONS,  STAMFOBD 
AND  CHARING    CBOSS. 


RETURN  TO  the  circulation  desk  of  any 
University  of  California  Library 

or  to  the 

NORTHERN  REGIONAL  LIBRARY  FACILITY 
BIdg.  400,  Richmond  Field  Station 
University  of  California 
Richmond,  CA  94804-4698 

ALL  BOOKS  MAY  BE  RECALLED  AFTER  7  DAYS 

•  2-month  loans  may  be  renewed  by  calling 
(510)642-6753 

•  1-year  loans  may  be  recharged  by  bringing 
books  to  NRLF 

•  Renewals  and  recharges  may  be  made 
4  days  prior  to  due  date 

DUE  AS  STAMPED  BELOW 
SENT  ON  ILL 

AUG  1  7  ?nn^ 

U.C.  BERKELEY 


DD20  6M  9-03 


NIVERSITY  OF  CAUFORNIA  IvIBRARY 


.^..=..-^.  *M^ 


im 


<s^;m 


